Strong-coupling approximations
International Nuclear Information System (INIS)
Abbott, R.B.
1984-03-01
Standard path-integral techniques such as instanton calculations give good answers for weak-coupling problems, but become unreliable for strong-coupling. Here we consider a method of replacing the original potential by a suitably chosen harmonic oscillator potential. Physically this is motivated by the fact that potential barriers below the level of the ground-state energy of a quantum-mechanical system have little effect. Numerically, results are good, both for quantum-mechanical problems and for massive phi 4 field theory in 1 + 1 dimensions. 9 references, 6 figures
Dvali, Gia
2009-01-01
We show that whenever a 4-dimensional theory with N particle species emerges as a consistent low energy description of a 3-brane embedded in an asymptotically-flat (4+d)-dimensional space, the holographic scale of high-dimensional gravity sets the strong coupling scale of the 4D theory. This connection persists in the limit in which gravity can be consistently decoupled. We demonstrate this effect for orbifold planes, as well as for the solitonic branes and string theoretic D-branes. In all cases the emergence of a 4D strong coupling scale from bulk holography is a persistent phenomenon. The effect turns out to be insensitive even to such extreme deformations of the brane action that seemingly shield 4D theory from the bulk gravity effects. A well understood example of such deformation is given by large 4D Einstein term in the 3-brane action, which is known to suppress the strength of 5D gravity at short distances and change the 5D Newton's law into the four-dimensional one. Nevertheless, we observe that the ...
Stirring Strongly Coupled Plasma
Fadafan, Kazem Bitaghsir; Rajagopal, Krishna; Wiedemann, Urs Achim
2009-01-01
We determine the energy it takes to move a test quark along a circle of radius L with angular frequency w through the strongly coupled plasma of N=4 supersymmetric Yang-Mills (SYM) theory. We find that for most values of L and w the energy deposited by stirring the plasma in this way is governed either by the drag force acting on a test quark moving through the plasma in a straight line with speed v=Lw or by the energy radiated by a quark in circular motion in the absence of any plasma, whichever is larger. There is a continuous crossover from the drag-dominated regime to the radiation-dominated regime. In the crossover regime we find evidence for significant destructive interference between energy loss due to drag and that due to radiation as if in vacuum. The rotating quark thus serves as a model system in which the relative strength of, and interplay between, two different mechanisms of parton energy loss is accessible via a controlled classical gravity calculation. We close by speculating on the implicati...
Intense Shock Waves and Strongly Coupled Plasmas
Fortov, Vladimir
2005-07-01
The report presents the recent results of experimental investigations of equations of state, compositions, thermodynamical and transport properties, electrical conductivity and opacity of strongly coupled plasmas generated by intense shock and rarefaction waves. The experimental methods for generation of high energy densities in matter, drivers for shock waves and fast diagnostic tools are discussed. Application of intense shock waves to solid and porous targets generates nonideal plasmas in megabar-gigabar pressure range. Compression of plasma by a series of reverberating shock waves allows us to decrease irreversible heating effects. To increase the irreversibility effects and to generate high temperature plasma states the experiments on shock compression of porous samples (fine metal powder, aerogels) were performed. The adiabatic expansion of matter initially compressed by intense shocks up to megabars allows investigating the intermediate region between the solid and vapor phase of nonideal plasmas, including the metal-insulator transition phase and the high temperature saturation curve with critical points of metals. The shock-wave-induced non-equilibrium phenomena at fast melting, spallation and adiabatic condensation are analyzed in the framework of the interspinodal decomposition model. The spall strength of single and polycrystal metals at extremely fast deformation produced by fast shock waves is discussed. The ``pressure ionization'' phenomena in hydrogen, helium, argon, xenon, krypton, neon, iodine, silica, sulfur, fullerenes, and some metals are analyzed on the base of multiple shock compression experiments. For some simple metals (Li, Na, Ca) the effect of ``dielectrization'' as a result of multiple shock compression are discussed.
International Nuclear Information System (INIS)
Aoki, Ken-ichi
1988-01-01
Existence of a strong coupling phase in QED has been suggested in solutions of the Schwinger-Dyson equation and in Monte Carlo simulation of lattice QED. In this article we recapitulate the previous arguments, and formulate the problem in the modern framework of the renormalization theory, Wilsonian renormalization. This scheme of renormalization gives the best understanding of the basic structure of a field theory especially when it has a multi-phase structure. We resolve some misleading arguments in the previous literature. Then we set up a strategy to attack the strong phase, if any. We describe a trial; a coupled Schwinger-Dyson equation. Possible picture of the strong coupling phase QED is presented. (author)
Physics of Strongly Coupled Plasma
Energy Technology Data Exchange (ETDEWEB)
Kraeft, Wolf-Dietrich [Universitat Rostock (Germany)
2007-07-15
Strongly coupled plasmas (or non-ideal plasmas) are multi-component charged many-particle systems, in which the mean value of the potential energy of the system is of the same order as or even higher than the mean value of the kinetic energy. The constituents are electrons, ions, atoms and molecules. Dusty (or complex) plasmas contain still mesoscopic (multiply charged) particles. In such systems, the effects of strong coupling (non-ideality) lead to considerable deviations of physical properties from the corresponding properties of ideal plasmas, i.e., of plasmas in which the mean kinetic energy is essentially larger than the mean potential energy. For instance, bound state energies become density dependent and vanish at higher densities (Mott effect) due to the interaction of the pair with the surrounding particles. Non-ideal plasmas are of interest both for general scientific reasons (including, for example, astrophysical questions), and for technical applications such as inertially confined fusion. In spite of great efforts both experimentally and theoretically, satisfactory information on the physical properties of strongly coupled plasmas is not at hand for any temperature and density. For example, the theoretical description of non-ideal plasmas is possible only at low densities/high temperatures and at extremely high densities (high degeneracy). For intermediate degeneracy, however, numerical experiments have to fill the gap. Experiments are difficult in the region of 'warm dense matter'. The monograph tries to present the state of the art concerning both theoretical and experimental attempts. It mainly includes results of the work performed in famous Russian laboratories in recent decades. After outlining basic concepts (chapter 1), the generation of plasmas is considered (chapter 2, chapter 3). Questions of partial (chapter 4) and full ionization (chapter 5) are discussed including Mott transition and Wigner crystallization. Electrical and
Strongly coupled dust coulomb clusters
International Nuclear Information System (INIS)
Juan Wentau; Lai Yingju; Chen Mingheng; I Lin
1999-01-01
The structures and motions of quasi-2-dimensional strongly coupled dust Coulomb clusters with particle number N from few to hundreds in a cylindrical rf plasma trap are studied and compared with the results from the molecular dynamic simulation using more ideal models. Shell structures with periodic packing in different shells and intershell rotational motion dominated excitations are observed at small N. As N increases, the boundary has less effect, the system recovers to the triangular lattice with isotropic vortex type cooperative excitations similar to an infinite N system except the outer shell region. The above generic behaviors are mainly determined by the system symmetry and agree with the simulation results. The detailed interaction form causes minor effect such as the fine structure of packing
Large N baryons, strong coupling theory, quarks
International Nuclear Information System (INIS)
Sakita, B.
1984-01-01
It is shown that in QCD the large N limit is the same as the static strong coupling limit. By using the static strong coupling techniques some of the results of large N baryons are derived. The results are consistent with the large N SU(6) static quark model. (author)
Strong Coupling Corrections in Quantum Thermodynamics
Perarnau-Llobet, M.; Wilming, H.; Riera, A.; Gallego, R.; Eisert, J.
2018-03-01
Quantum systems strongly coupled to many-body systems equilibrate to the reduced state of a global thermal state, deviating from the local thermal state of the system as it occurs in the weak-coupling limit. Taking this insight as a starting point, we study the thermodynamics of systems strongly coupled to thermal baths. First, we provide strong-coupling corrections to the second law applicable to general systems in three of its different readings: As a statement of maximal extractable work, on heat dissipation, and bound to the Carnot efficiency. These corrections become relevant for small quantum systems and vanish in first order in the interaction strength. We then move to the question of power of heat engines, obtaining a bound on the power enhancement due to strong coupling. Our results are exemplified on the paradigmatic non-Markovian quantum Brownian motion.
Impurity screening in strongly coupled plasma systems
Kyrkos, S
2003-01-01
We present an overview of the problem of screening of an impurity in a strongly coupled one-component plasma within the framework of the linear response (LR) theory. We consider 3D, 2D and quasi-2D layered systems. For a strongly coupled plasma the LR can be determined by way of the known S(k) structure functions. In general, an oscillating screening potential with local overscreening and antiscreening regions emerges. In the case of the bilayer, this phenomenon becomes global, as overscreening develops in the layer of the impurity and antiscreening in the adjacent layer. We comment on the limitations of the LR theory in the strong coupling situation.
Strong Coupling between Plasmons and Organic Semiconductors
Directory of Open Access Journals (Sweden)
Joel Bellessa
2014-05-01
Full Text Available In this paper we describe the properties of organic material in strong coupling with plasmon, mainly based on our work in this field of research. The strong coupling modifies the optical transitions of the structure, and occurs when the interaction between molecules and plasmon prevails on the damping of the system. We describe the dispersion relation of different plasmonic systems, delocalized and localized plasmon, coupled to aggregated dyes and the typical properties of these systems in strong coupling. The modification of the dye emission is also studied. In the second part, the effect of the microscopic structure of the organics, which can be seen as a disordered film, is described. As the different molecules couple to the same plasmon mode, an extended coherent state on several microns is observed.
Gluon scattering amplitudes at strong coupling
Energy Technology Data Exchange (ETDEWEB)
Alday, Luis F. [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands); Maldacena, Juan [School of Natural Sciences, Institute for Advanced Study, Princeton, NJ 08540 (United States)
2007-06-15
We describe how to compute planar gluon scattering amplitudes at strong coupling in N = 4 super Yang Mills by using the gauge/string duality. The computation boils down to finding a certain classical string configuration whose boundary conditions are determined by the gluon momenta. The results are infrared divergent. We introduce the gravity version of dimensional regularization to define finite quantities. The leading and subleading IR divergencies are characterized by two functions of the coupling that we compute at strong coupling. We compute also the full finite form for the four point amplitude and we find agreement with a recent ansatz by Bern, Dixon and Smirnov.
Strong Josephson Coupling in Planar Graphene Junctions
Park, Jinho; Lee, Gil-Ho; Lee, Jae Hyeong; Takane, Yositake; Imura, Ken-Ichiro; Taniguchi, Takashi; Watanabe, Kenji; Lee, Hu-Jong
A recent breakthrough of processing graphene, employing encapsulation by hexagonal boron nitride layers (BGB structure), allows realizing the ballistic carrier transport in graphene. Thereafter, ballistic Josephson coupling has been studied by closely edge-contacted BGB structure with two superconducting electrodes. Here, we report on the strong Josephson coupling with planar graphene junction in truly short and ballistic regime. Our device showed high transmission probability and the junction critical current (IC) oscillating for sweeping the gate voltage along with the normal conductance oscillation (Fabry-Perot oscillations), providing a direct evidence for the ballistic nature of the junction pair current. We also observed the convex-upward shape of decreasing critical currents with increasing temperature, canonical properties of the short Josephson coupling. By fitting these curves into theoretical models, we demonstrate the strong Josephson coupling in our devices, which is also supported by the exceptionally large value of ICRN ( 2 Δ / e RNis the normal resistance).
A strongly coupled quark-gluon plasma
Energy Technology Data Exchange (ETDEWEB)
Shuryak, Edward [Department of Physics and Astronomy, University at Stony Brook, NY 11794 (United States)
2004-08-01
Successful description of robust collective flow phenomena at RHIC by ideal hydrodynamics, recent observations of bound c-barc,q-barq states on the lattice, and other theoretical developments indicate that QGP produced at RHIC, and probably in a wider temperature region T{sub c} < T < 4T{sub c}, is not a weakly coupled quasiparticle gas as believed previously. We discuss how strong the interaction is and why it seems to generate hundreds of binary channels with bound states, surviving well inside the QGP phase. We in particular discuss their effect on pressure and viscosity. We conclude by reviewing the similar phenomena for other 'strongly coupled systems', such as (i) strongly coupled supersymmetric theories studied via Maldacena duality; (ii) trapped ultra-cold atoms with very large scattering length, tuned to Feschbach resonances.
Chaos desynchronization in strongly coupled systems
International Nuclear Information System (INIS)
Wu Ye; Liu Weiqing; Xiao, Jinghua; Zhan Meng
2007-01-01
The dynamics of chaos desynchronization in strongly coupled oscillator systems is studied. We find a new bifurcation from synchronous chaotic state, chaotic short wave bifurcation, i.e. a chaotic desynchronization attractor is new born in the systems due to chaos desynchronization. In comparison with the usual periodic short wave bifurcation, very rich but distinct phenomena are observed
Strong-coupling diffusion in relativistic systems
Indian Academy of Sciences (India)
hanced values needed to interpret the data at higher energies point towards the importance of strong-coupling effects. ... when all secondary particles have been created. For short times in the initial phase ... It is decisive for a proper representation of the available data for relativistic heavy-ion collisions at and beyond SPS.
Strong-coupling diffusion in relativistic systems
Indian Academy of Sciences (India)
Different from the early universe, heavy-ion collisions at very high energies do not reach statistical equilibrium, although thermal models explain many of their features. To account for nonequilibrium strong-coupling effects, a Fokker–Planck equation with time-dependent diffusion coefﬁcient is proposed. A schematic model ...
Strongly coupled semidirect mediation of supersymmetry breaking
International Nuclear Information System (INIS)
Ibe, M.; Izawa, K.-I.; Nakai, Y.
2009-01-01
Strongly coupled semidirect gauge mediation models of supersymmetry breaking through massive mediators with standard-model charges are investigated by means of composite degrees of freedom. Sizable mediation is realized to generate the standard-model gaugino masses for a small mediator mass without breaking the standard-model symmetries.
Patterns of Strong Coupling for LHC Searches
Liu, Da; Rattazzi, Riccardo; Riva, Francesco
2016-11-23
Even though the Standard Model (SM) is weakly coupled at the Fermi scale, a new strong dynamics involving its degrees of freedom may conceivably lurk at slightly higher energies, in the multi TeV range. Approximate symmetries provide a structurally robust context where, within the low energy description, the dimensionless SM couplings are weak, while the new strong dynamics manifests itself exclusively through higher-derivative interactions. We present an exhaustive classification of such scenarios in the form of effective field theories, paying special attention to new classes of models where the strong dynamics involves, along with the Higgs boson, the SM gauge bosons and/or the fermions. The IR softness of the new dynamics suppresses its effects at LEP energies, but deviations are in principle detectable at the LHC, even at energies below the threshold for production of new states. Our construction provides the so far unique structurally robust context where to motivate several searches in Higgs physics, d...
Strong spin-photon coupling in silicon.
Samkharadze, N; Zheng, G; Kalhor, N; Brousse, D; Sammak, A; Mendes, U C; Blais, A; Scappucci, G; Vandersypen, L M K
2018-03-09
Long coherence times of single spins in silicon quantum dots make these systems highly attractive for quantum computation, but how to scale up spin qubit systems remains an open question. As a first step to address this issue, we demonstrate the strong coupling of a single electron spin and a single microwave photon. The electron spin is trapped in a silicon double quantum dot, and the microwave photon is stored in an on-chip high-impedance superconducting resonator. The electric field component of the cavity photon couples directly to the charge dipole of the electron in the double dot, and indirectly to the electron spin, through a strong local magnetic field gradient from a nearby micromagnet. Our results provide a route to realizing large networks of quantum dot-based spin qubit registers. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
Strong coupling QED with two fermionic flavors
Energy Technology Data Exchange (ETDEWEB)
Wang, K.C.
1990-11-01
We report the recent results of our simulation of strong coupling QED, with non-compact action, on lattices 10{sup 4} and 16{sup 4}. Since we are dealing with two staggered fermionic flavors, we use hybrid algorithm to do the simulation. In addition to the measurement of the chiral order parameter {l angle}{bar {psi}}{psi}{r angle}, we also measure magnetic monopole susceptibility, {chi}, throughout the region of chiral transition. 6 refs., 6 figs.
Strong coupling analogue of the Born series
International Nuclear Information System (INIS)
Dolinszky, T.
1989-10-01
In a given partial wave, the strength of the centrifugal term to be incorporated into the WKBA solutions in different spatial regions can be adjusted so as to make the first order wave functions everywhere smooth and, in strong coupling, exactly reproduce Quantum Mechanics throughout the space. The relevant higher order approximations supply an absolute convergent series expansion of the exact scattering state. (author) 4 refs.; 2 figs.; 2 tabs
Holographic gauge mediation via strongly coupled messengers
International Nuclear Information System (INIS)
McGuirk, Paul; Shiu, Gary; Sumitomo, Yoske
2010-01-01
We consider a relative of semidirect gauge mediation where the hidden sector exists at large 't Hooft coupling. Such scenarios can be difficult to describe using perturbative field theory methods but may fall into the class of holographic gauge mediation scenarios, meaning that they are amenable to the techniques of gauge/gravity duality. We use a recently found gravity solution to examine one such case, where the hidden sector is a cascading gauge theory resulting in a confinement scale not much smaller than the messenger mass. In the original construction of holographic gauge mediation, as in other examples of semidirect gauge mediation at strong coupling, the primary contributions to visible sector soft terms come from weakly coupled messenger mesons. In contrast to these examples, we describe the dual of a gauge theory where there are significant contributions from scales in which the strongly coupled messenger quarks are the effective degrees of freedom. In this regime, the visible sector gaugino mass can be calculated entirely from holography.
The Dark Side of Strongly Coupled Theories
DEFF Research Database (Denmark)
Kouvaris, Christoforos
2008-01-01
We investigate the constraints of dark matter search experiments on the different candidates emerging from the minimal quasi-conformal strong coupling theory with fermions in the adjoint representation. For one candidate, the current limits of CDMS exclude a tiny window of masses around 120 GeV. We...... also investigate under what circumstances the newly proposed candidate composed of a -2 negatively charged particle and a $^4He^{+2}$ can explain the discrepancy between the results of the CDMS and DAMA experiments. We found that this type of dark matter should give negative results in CDMS, while...
Strong Coupling Gauge Theories in LHC ERA
Fukaya, H.; Harada, M.; Tanabashi, M.; Yamawaki, K.
2011-01-01
Higgs, or techni-dilaton - composite Higgs near conformality / Koichi Yamawaki -- Phase diagram of strongly interacting theories / Francesco Sannino -- Resizing conformal windows / O. Antipin and K. Tuominen -- Nearly conformal gauge theories on the lattice / Zoltan Fodor ... [et al.] -- Going beyond QCD in lattice gauge theory / G. T. Fleming -- Phases of QCD from small to large N[symbol]: (some) lattice results / A. Deuzeman, E. Pallante and M. P. Lombardo -- Lattice gauge theory and (quasi)-conformal technicolor / D. K. Sinclair and J. B. Kogut -- Study of the running coupling constant in 10-flavor QCD with the Schrodinger functional method / N. Yamada ... [et al.] -- Study of the running coupling in twisted Polyakov scheme / T. Aoyama ... [et al.].Running coupling in strong gauge theories via the lattice / Zoltan Fodor ... [et al.] -- Higgsinoless supersymmetry and hidden gravity / Michael L. Graesser, Ryuichiro Kitano and Masafumi Kurachi -- The latest status of LHC and the EWSB physics / S. Asai -- Continuum superpartners from supersymmetric unparticles / Hsin-Chia Cheng -- Review of minimal flavor constraints for technicolor / Hidenori S. Fukano and Francesco Sannino -- Standard model and high energy Lorentz violation / Damiano Anselmi -- Dynamical electroweak symmetry breaking and fourth family / Michio Hashimoto -- Holmorphic supersymmetric Nambu-Jona-Lasino model and dynamical electroweak symmetry breaking / Dong-Won Jung, Otto C. W. Kong and Jae Sik Lee -- Ratchet model of Baryogenesis / Tatsu Takeuchi, Azusa Minamizaki and Akio Sugamoto -- Classical solutions of field equations in Einstein Gauss-Bonnet gravity / P. Suranyi, C. Vaz and L. C. R. Wijewardhana -- Black holes constitute all dark matter / Paul H. Frampton -- Electroweak precision test and Z [symbol] in the three site Higgsless model / Tomohiro Abe -- Chiral symmetry and BRST symmetry breaking, quaternion reality and the lattice simulation / Sadataka Furui -- Holographic techni-dilaton, or
Strong coupling from the Hubbard model
Minahan, Joseph A.
2006-10-01
It was recently observed that the one-dimensional half-filled Hubbard model reproduces the known part of the perturbative spectrum of planar {\\cal N}=4 super Yang Mills in the SU(2) sector. Assuming that this identification is valid beyond perturbation theory, we investigate the behaviour of this spectrum as the 't Hooft parameter λ becomes large. We show that the full dimension Δ of the Konishi superpartner is the solution of a sixth-order polynomial while Δ for a bare dimension 5 operator is the solution of a cubic. In both cases, the equations can be solved easily as a series expansion for both small and large λ and the equations can be inverted to express λ as an explicit function of Δ. We then consider more general operators and show how Δ depends on λ in the strong coupling limit. We are also able to distinguish those states in the Hubbard model which correspond to the gauge-invariant operators for all values of λ. Finally, we compare our results with known results for strings on AdS5 × S5, where we find agreement for a range of R-charges.
Kinetic theory for strongly coupled Coulomb systems
Dufty, James; Wrighton, Jeffrey
2018-01-01
The calculation of dynamical properties for matter under extreme conditions is a challenging task. The popular Kubo-Greenwood model exploits elements from equilibrium density-functional theory (DFT) that allow a detailed treatment of electron correlations, but its origin is largely phenomenological; traditional kinetic theories have a more secure foundation but are limited to weak ion-electron interactions. The objective here is to show how a combination of the two evolves naturally from the short-time limit for the generator of the effective single-electron dynamics governing time correlation functions without such limitations. This provides a theoretical context for the current DFT-related approach, the Kubo-Greenwood model, while showing the nature of its corrections. The method is to calculate the short-time dynamics in the single-electron subspace for a given configuration of the ions. This differs from the usual kinetic theory approach in which an average over the ions is performed as well. In this way the effective ion-electron interaction includes strong Coulomb coupling and is shown to be determined from DFT. The correlation functions have the form of the random-phase approximation for an inhomogeneous system but with renormalized ion-electron and electron-electron potentials. The dynamic structure function, density response function, and electrical conductivity are calculated as examples. The static local field corrections in the dielectric function are identified in this way. The current analysis is limited to semiclassical electrons (quantum statistical potentials), so important quantum conditions are excluded. However, a quantization of the kinetic theory is identified for broader application while awaiting its detailed derivation.
Compensating strong coupling with large charge
Energy Technology Data Exchange (ETDEWEB)
Alvarez-Gaume, Luis [Theory Department - CERN,CH-1211 Geneva 23 (Switzerland); Simons Center for Geometry and Physics, State University of New York,Stony Brook, NY-11794-3636 (United States); Loukas, Orestis; Orlando, Domenico; Reffert, Susanne [Albert Einstein Center for Fundamental Physics,Institute for Theoretical Physics, University of Bern,Sidlerstrasse 5, CH-3012 Bern (Switzerland)
2017-04-11
We study some (conformal) field theories with global symmetries in the sector where the value of the global charge Q is large. We find (as expected) that the low energy excitations of this sector are described by the general form of Goldstone’s theorem in the non-relativistic regime. We also derive the unexpected result, first presented in https://www.doi.org/10.1007/JHEP12(2015)071, that the effective field theory describing such sector of fixed Q contains effective couplings λ{sub eff}∼λ{sup b}/Q{sup a}, where λ is the original coupling. Hence, large charge leads to weak coupling. In the last section of the paper we present an outline of how to compute anomalous dimensions of the O(n) model in this limit.
Compensating strong coupling with large charge
Alvarez-Gaume, Luis; Orlando, Domenico; Reffert, Susanne
2017-04-11
We study (conformal) field theories with global symmetries in the sector where the value of the global charge $Q$ is large. We find (as expected) that the low energy excitations of this sector are described by the general form of Goldstone's theorem in the non-relativistic regime. We also derive the unexpected result, first presented in [Hellerman:2015], that the effective field theory describing such sector of fixed $Q$ contains effective couplings $\\lambda_{\\text{eff}}\\sim \\lambda^b /Q^{a}$, where $\\lambda$ is the original coupling. Hence, large charge leads to weak coupling. In the last section of the paper we present an outline of how to compute anomalous dimensions in this limit.
Development of strongly coupled FSI technology involving thin walled structures
CSIR Research Space (South Africa)
Suliman, Ridhwaan
2011-01-01
Full Text Available the most desirable results and is coupled with an in-house fluid-flow solver. The developed technology is evaluated on representative strongly coupled fluid-structure interaction test problems....
Electromagnetic modes in cold magnetized strongly coupled plasmas
Tkachenko, I. M.; Ortner, J.; Rylyuk, V. M.
1999-01-01
The spectrum of electromagnetic waves propagating in a strongly coupled magnetized fully ionized hydrogen plasma is found. The ion motion and damping being neglected, the influence of the Coulomb coupling on the electromagnetic spectrum is analyzed.
Strongly coupled band in 140Gd
International Nuclear Information System (INIS)
Falla-Sotelo, F.; Oliveira, J.R.B.; Rao, M.N.
2005-01-01
Several high-K states are known to exist in the mass 130-140 region. For the N=74 even-even isotopes, Kπ = 8 - isomers, with lifetimes ranging from ns to ms, are known in 128 Xe, 130 Ba, 132 Ce, 134 Nd, 136 Sm, and 138 Gd[. In 140 Gd, we have observed for the first time a band also based on an Iπ = 8 - state. This could be the first case of a Kπ = 8 - state observed in an N=76 even-even isotope. The systematics of the Kπ = 8 - isomeric states in N=74 isotopes has been studied by A.M. Bruce et al. These states decay towards the K = 0 ground state band, and the transitions are K-forbidden. The 140 Gd case presents strong similarities but also some significant differences with relation to the N=74 isotopes. We propose the same configuration but with larger deformation in 140 Gd
Strongly coupled band in {sup 140}Gd
Energy Technology Data Exchange (ETDEWEB)
Falla-Sotelo, F.; Oliveira, J.R.B.; Rao, M.N. [Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo (Brazil)] (and others)
2005-07-01
Several high-K states are known to exist in the mass 130-140 region. For the N=74 even-even isotopes, K{pi} = 8{sup -} isomers, with lifetimes ranging from ns to ms, are known in {sup 128}Xe, {sup 130}Ba, {sup 132}Ce, {sup 134}Nd, {sup 136}Sm, and {sup 138}Gd[. In {sup 140}Gd, we have observed for the first time a band also based on an I{pi} = 8{sup -} state. This could be the first case of a K{pi} = 8{sup -} state observed in an N=76 even-even isotope. The systematics of the K{pi} = 8{sup -} isomeric states in N=74 isotopes has been studied by A.M. Bruce et al. These states decay towards the K = 0 ground state band, and the transitions are K-forbidden. The {sup 140}Gd case presents strong similarities but also some significant differences with relation to the N=74 isotopes. We propose the same configuration but with larger deformation in {sup 140}Gd.
Shear viscosities of photons in strongly coupled plasmas
Directory of Open Access Journals (Sweden)
Di-Lun Yang
2016-09-01
Full Text Available We investigate the shear viscosity of thermalized photons in the quark gluon plasma (QGP at weak coupling and N=4 super Yang–Mills plasma (SYMP at both strong and weak couplings. We find that the shear viscosity due to the photon–parton scattering up to the leading order of electromagnetic coupling is suppressed when the coupling of the QGP/SYMP is increased, which stems from the blue-shift of the thermal-photon spectrum at strong coupling. In addition, the shear viscosity rapidly increases near the deconfinement transition in a phenomenological model analogous to the QGP.
Synchrotron radiation in strongly coupled conformal field theories
Athanasiou, Christiana; Chesler, Paul M.; Liu, Hong; Nickel, Dominik; Rajagopal, Krishna
2010-01-01
Using gauge/gravity duality, we compute the energy density and angular distribution of the power radiated by a quark undergoing circular motion in strongly coupled ${\\cal N}=4$ supersymmetric Yang-Mills (SYM) theory. We compare the strong coupling results to those at weak coupling, and find the same angular distribution of radiated power, up to an overall prefactor. In both regimes, the angular distribution is in fact similar to that of synchrotron radiation produced by an electron in circula...
Synchrotron radiation in strongly coupled conformal field theories
Athanasiou, Christiana; Chesler, Paul M.; Liu, Hong; Nickel, Dominik; Rajagopal, Krishna
2010-06-01
Using gauge/gravity duality, we compute the energy density and angular distribution of the power radiated by a quark undergoing circular motion in strongly coupled N=4 supersymmetric Yang-Mills theory. We compare the strong coupling results to those at weak coupling, finding them to be very similar. In both regimes, the angular distribution of the radiated power is in fact similar to that of synchrotron radiation produced by an electron in circular motion in classical electrodynamics: the quark emits radiation in a narrow beam along its velocity vector with a characteristic opening angle α˜1/γ. To an observer far away from the quark, the emitted radiation appears as a short periodic burst, just like the light from a lighthouse does to a ship at sea. Our strong coupling results are valid for any strongly coupled conformal field theory with a dual classical gravity description.
Near-field strong coupling of single quantum dots.
Groß, Heiko; Hamm, Joachim M; Tufarelli, Tommaso; Hess, Ortwin; Hecht, Bert
2018-03-01
Strong coupling and the resultant mixing of light and matter states is an important asset for future quantum technologies. We demonstrate deterministic room temperature strong coupling of a mesoscopic colloidal quantum dot to a plasmonic nanoresonator at the apex of a scanning probe. Enormous Rabi splittings of up to 110 meV are accomplished by nanometer-precise positioning of the quantum dot with respect to the nanoresonator probe. We find that, in addition to a small mode volume of the nanoresonator, collective coherent coupling of quantum dot band-edge states and near-field proximity interaction are vital ingredients for the realization of near-field strong coupling of mesoscopic quantum dots. The broadband nature of the interaction paves the road toward ultrafast coherent manipulation of the coupled quantum dot-plasmon system under ambient conditions.
Scattering on a nonrelativistic particle in strong coupling theory
International Nuclear Information System (INIS)
Razumov, A.V.
1977-01-01
Interaction of a nonrelativistic particle with a scalar quantum field has been studied in one-dimensional space in the framework of the Bogolyubov's method. An energy spectrum and scattering amplitude on a dressed particle have been obtained for the case of strong coupling up to the zero order over the coupling constant
Driven transverse shear waves in a strongly coupled dusty plasma
International Nuclear Information System (INIS)
Bandyopadhyay, P.; Prasad, G.; Sen, A.; Kaw, P.K.
2008-01-01
The linear dispersion properties of transverse shear waves in a strongly coupled dusty plasma are experimentally studied in a DC discharge device by exciting them in a controlled manner with a variable frequency external source. The dusty plasma is maintained in the strongly coupled fluid regime with (1 c ) where Γ is the Coulomb coupling parameter and Γ c is the crystallization limit. A dispersion relation for the transverse waves is experimentally obtained over a frequency range of 0.1 Hz to 2 Hz and found to show good agreement with viscoelastic theoretical results
Integrating out resonances in strongly-coupled electroweak scenarios
Directory of Open Access Journals (Sweden)
Rosell Ignasi
2017-01-01
Full Text Available Accepting that there is a mass gap above the electroweak scale, the Electroweak Effective Theory (EWET is an appropriate tool to describe this situation. Since the EWET couplings contain information on the unknown high-energy dynamics, we consider a generic strongly-coupled scenario of electroweak symmetry breaking, where the known particle fields are coupled to heavier states. Then, and by integrating out these heavy fields, we study the tracks of the lightest resonances into the couplings. The determination of the low-energy couplings (LECs in terms of resonance parameters can be made more precise by considering a proper short-distance behaviour on the Lagrangian with heavy states, since the number of resonance couplings is then reduced. Notice that we adopt a generic non-linear realization of the electroweak symmetry breaking with a singlet Higgs.
Broadband room temperature strong coupling between quantum dots and metamaterials.
Indukuri, Chaitanya; Yadav, Ravindra Kumar; Basu, J K
2017-08-17
Herein, we report the first demonstration of room temperature enhanced light-matter coupling in the visible regime for metamaterials using cooperative coupled quasi two dimensional quantum dot assemblies located at precise distances from the hyperbolic metamaterial (HMM) templates. The non-monotonic variation of the magnitude of strong coupling, manifested in terms of strong splitting of the photoluminescence of quantum dots, can be explained in terms of enhanced LDOS near the surface of such metamaterials as well as the plasmon mediated super-radiance of closely spaced quantum dots (QDs). Our methodology of enhancing broadband, room temperature, light-matter coupling in the visible regime for metamaterials opens up new possibilities of utilising these materials for a wide range of applications including QD based thresholdless nanolasers and novel metamaterial based integrated photonic devices.
Ultrafast control of strong light–matter coupling
Lange, Christoph; Cancellieri, Emiliano; Panna, Dmitry; Whittaker, David M.; Steger, Mark; Snoke, David W.; Pfeiffer, Loren N.; West, Kenneth W.; Hayat, Alex
2018-01-01
We dynamically modulate strong light–matter coupling in a GaAs/AlGaAs microcavity using intense ultrashort laser pulses tuned below the interband exciton energy, which induce a transient Stark shift of the cavity polaritons. For 225-fs pulses, shorter than the cavity Rabi cycle period of 1000 fs, this shift decouples excitons and cavity photons for the duration of the pulse, interrupting the periodic energy exchange between photonic and electronic states. For 1500-fs pulses, longer than the Rabi cycle period, however, the Stark shift does not affect the strong coupling. The two regimes are marked by distinctly different line shapes in ultrafast reflectivity measurements—regardless of the Stark field intensity. The crossover marks the transition from adiabatic to diabatic switching of strong light–matter coupling.
A Hybrid Strong/Weak Coupling Approach to Jet Quenching
Casalderrey-Solana, Jorge; Milhano, José Guilherme; Pablos, Daniel; Rajagopal, Krishna
2014-01-01
We propose and explore a new hybrid approach to jet quenching in a strongly coupled medium. The basis of this phenomenological approach is to treat physics processes at different energy scales differently. The high-$Q^2$ processes associated with the QCD evolution of the jet from production as a single hard parton through its fragmentation, up to but not including hadronization, are treated perturbatively. The interactions between the partons in the shower and the deconfined matter within which they find themselves lead to energy loss. The momentum scales associated with the medium (of the order of the temperature) and with typical interactions between partons in the shower and the medium are sufficiently soft that strongly coupled physics plays an important role in energy loss. We model these interactions using qualitative insights from holographic calculations of the energy loss of energetic light quarks and gluons in a strongly coupled plasma, obtained via gauge/gravity duality. We embed this hybrid model ...
Ideal gas behavior of a strongly coupled complex (dusty) plasma.
Oxtoby, Neil P; Griffith, Elias J; Durniak, Céline; Ralph, Jason F; Samsonov, Dmitry
2013-07-05
In a laboratory, a two-dimensional complex (dusty) plasma consists of a low-density ionized gas containing a confined suspension of Yukawa-coupled plastic microspheres. For an initial crystal-like form, we report ideal gas behavior in this strongly coupled system during shock-wave experiments. This evidence supports the use of the ideal gas law as the equation of state for soft crystals such as those formed by dusty plasmas.
The strong coupling from tau decays without prejudice
Boito, Diogo; Golterman, Maarten; Jamin, Matthias; Mahdavi, Andisheh; Maltman, Kim; Osborne, James; Peris, Santiago
2014-08-01
We review our recent determination of the strong coupling αs from the OPAL data for non-strange hadronic tau decays. We find that αs (mτ2)= 0.325 ± 0.018 using fixed-order perturbation theory, and αs (mτ2)= 0.347 ± 0.025 using contour-improved perturbation theory. At present, these values supersede any earlier determinations of the strong coupling from hadronic tau decays, including those from ALEPH data.
The strong coupling from tau decays without prejudice
Energy Technology Data Exchange (ETDEWEB)
Boito, Diogo [Physik Department T31, Technische Universität München, James-Franck-Straße 1, D-85748 Garching (Germany); Golterman, Maarten [Institut de Física d' Altes Energies, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain); Department of Physics and Astronomy, San Francisco State University, San Francisco, CA 94132 (United States); Jamin, Matthias [Institució Catalana de Recerca i Estudis Avançats (ICREA), IFAE, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain); Mahdavi, Andisheh [Department of Physics and Astronomy, San Francisco State University, San Francisco, CA 94132 (United States); Maltman, Kim [Department of Mathematics and Statistics, York University, Toronto, ON Canada M3J 1P3 (Canada); CSSM, University of Adelaide, Adelaide, SA 5005 Australia (Australia); Osborne, James [Department of Physics and Astronomy, San Francisco State University, San Francisco, CA 94132 (United States); Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Peris, Santiago [Department of Physics, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain)
2014-08-15
We review our recent determination of the strong coupling α{sub s} from the OPAL data for non-strange hadronic tau decays. We find that α{sub s}(m{sub τ}{sup 2})=0.325±0.018 using fixed-order perturbation theory, and α{sub s}(m{sub τ}{sup 2})=0.347±0.025 using contour-improved perturbation theory. At present, these values supersede any earlier determinations of the strong coupling from hadronic tau decays, including those from ALEPH data.
Beyond strong coupling in a massively multimode cavity
Sundaresan, Neereja; Liu, Yanbing; Sadri, Darius; Szocs, Laszlo; Underwood, Devin; Malekakhlagh, Moein; Tureci, Hakan; Houck, Andrew
2015-03-01
We present experiments in a new regime of cavity quantum electrodynamics (cQED), the multimode strong coupling regime, in which the qubit-cavity coupling is comparable to the free spectral range, thus requiring the collective treatment of all modes along with the qubit. Here we show that this regime is accessible in circuit QED by coupling a 90MHz microwave cavity with a transmon qubit, resonant with the 75th harmonic with a coupling strength exceeding 30MHz. When driving this system, we observe multimode fluorescence consistent with cavity-enhanced sideband emission, with unexpected multi-photon processes and the emergence of ultra-narrow linewidths. This multimode coupling opens the door for a wide range of potential experiments, including studying the manifestation of complex many-body phenomena, the breakdown of the rotating wave approximation, and the bridge between discrete and continuous Hilbert spaces.
From strong to ultrastrong coupling in circuit QED architectures
International Nuclear Information System (INIS)
Niemczyk, Thomas
2011-01-01
The field of cavity quantum electrodynamics (cavity QED) studies the interaction between light and matter on a fundamental level: a single atom interacts with a single photon. If the atom-photon coupling is larger than any dissipative effects, the system enters the strong-coupling limit. A peculiarity of this regime is the possibility to form coherent superpositions of light and matter excitations - a kind of 'molecule' consisting of an atomic and a photonic contribution. The novel research field of circuit QED extends cavity QED concepts to solid-state based system. Here, a superconducting quantum bit is coupled to an on-chip superconducting one-dimensional waveguide resonator. Owing to the small mode-volume of the resonant cavity, the large dipole moment of the 'artificial atom' and the enormous engineering potential inherent to superconducting quantum circuits, remarkable atom-photon coupling strengths can be realized. This thesis describes the theoretical framework, the development of fabrication techniques and the implementation of experimental characterization techniques for superconducting quantum circuits for circuit QED applications. In particular, we study the interaction between superconducting flux quantum bits and high-quality coplanar waveguide resonators in the strong-coupling limit. Furthermore, we report on the first experimental realization of a circuit QED system operating in the ultrastrong-coupling regime, where the atom-photon coupling rate reaches a considerable fraction of the relevant system frequencies. In these experiments we could observe phenomena that can not be explained within the renowned Jaynes-Cummings model. (orig.)
Strongly coupled rotational band in ${}^{33}\mathrm{Mg}$
Energy Technology Data Exchange (ETDEWEB)
Richard, A. L. [Ohio Univ., Athens, OH (United States). Inst. for Nuclear and Particle Physics; Crawford, H. L. [Ohio Univ., Athens, OH (United States). Inst. for Nuclear and Particle Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Fallon, P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Macchiavelli, A. O. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Bader, V. M. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Bazin, D. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab.; Bowry, M. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Campbell, C. M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Carpenter, M. P. [Argonne National Lab. (ANL), Argonne, IL (United States). Physics Div.; Clark, R. M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Cromaz, M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Gade, A. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Ideguchi, E. [Osaka Univ. (Japan). RCNP; Iwasaki, H. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Jones, M. D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Langer, C. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Lee, I. Y. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Loelius, C. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Lunderberg, E. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Morse, C. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Rissanen, J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Salathe, M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Smalley, D. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Stroberg, S. R. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Weisshaar, D. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Whitmore, K. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Wiens, A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Williams, S. J. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Wimmer, K. [Univ. of Tokyo (Japan). Dept. of Physics; Yamamato, T. [Osaka Univ. (Japan). RCNP
2017-07-01
The “island of inversion” at N≈20 for the neon, sodium, and magnesium isotopes has long been an area of interest both experimentally and theoretically due to the subtle competition between 0p-0h and np-nh configurations leading to deformed shapes. However, the presence of rotational band structures, which are fingerprints of deformed shapes, have only recently been observed in this region. In this work, we report on a measurement of the low-lying level structure of Mg33 populated by a two-stage projectile fragmentation reaction and studied with the Gamma Ray Energy Tracking In-Beam Nuclear Array (GRETINA). The experimental level energies, ground-state magnetic moment, intrinsic quadrupole moment, and γ-ray intensities show good agreement with the strong-coupling limit of a rotational model.
Strongly coupled rotational band in ${}^{33}\mathrm{Mg}$
Energy Technology Data Exchange (ETDEWEB)
Richard, A. L.; Crawford, H. L.; Fallon, P.; Macchiavelli, A. O.; Bader, V. M.; Bazin, D.; Bowry, M.; Campbell, C. M.; Carpenter, M. P.; Clark, R. M.; Cromaz, M.; Gade, A.; Ideguchi, E.; Iwasaki, H.; Jones, M. D.; Langer, C.; Lee, I. Y.; Loelius, C.; Lunderberg, E.; Morse, C.; Rissanen, J.; Salathe, M.; Smalley, D.; Stroberg, S. R.; Weisshaar, D.; Whitmore, K.; Wiens, A.; Williams, S. J.; Wimmer, K.; Yamamato, T.
2017-07-01
The “Island of Inversion” at N~20 for the neon, sodium, and magnesium isotopes has long been an area of interest both experimentally and theoretically due to the subtle competition between 0p-0h and np-nh configurations leading to deformed shapes. However, the presence of rotational band structures, which are fingerprints of deformed shapes, have only recently been observed in this region. In this work, we report on a measurement of the low-lying level structure of 33Mg populated by a two-stage projectile fragmentation reaction and studied with GRETINA. The experimental level energies, ground state magnetic moment, intrinsic quadrupole moment, and γ-ray intensities show good agreement with the strong-coupling limit of a rotational model.
Raman scattering with strongly coupled vibron-polaritons
Strashko, Artem; Keeling, Jonathan
2016-08-01
Strong coupling between cavity photons and molecular vibrations can lead to the formation of vibron-polaritons. In a recent experiment with PVAc molecules in a metal-metal microcavity [Shalabney et al., Angew. Chem., Int. Ed. 54, 7971 (2015), 10.1002/anie.201502979], such a coupling was observed to enhance the Raman scattering probability by several orders of magnitude. Inspired by this, we theoretically analyze the effect of strong photon-vibron coupling on the Raman scattering amplitude of organic molecules. This problem has recently been addressed by del Pino, Feist, and Garcia-Vidal [J. Phys. Chem. C 119, 29132 (2015), 10.1021/acs.jpcc.5b11654] using exact numerics for a small number of molecules. In this paper we derive compact analytic results for any number of molecules, also including the ultrastrong-coupling regime. Our calculations predict a division of the Raman signal into upper and lower polariton modes, with some enhancement to the lower polariton Raman amplitude due to the mode softening under strong coupling.
Radial Distribution Functions of Strongly Coupled Two-Temperature Plasmas
Shaffer, Nathaniel R.; Tiwari, Sanat Kumar; Baalrud, Scott D.
2017-10-01
We present tests of three theoretical models for the radial distribution functions (RDFs) in two-temperature strongly coupled plasmas. RDFs are useful in extending plasma thermodynamics and kinetic theory to strong coupling, but they are usually known only for thermal equilibrium or for approximate one-component model plasmas. Accurate two-component modeling is necessary to understand the impact of strong coupling on inter-species transport, e.g., ambipolar diffusion and electron-ion temperature relaxation. We demonstrate that the Seuferling-Vogel-Toeppfer (SVT) extension of the hypernetted chain equations not only gives accurate RDFs (as compared with classical molecular dynamics simulations), but also has a simple connection with the Yukawa OCP model. This connection gives a practical means to recover the structure of the electron background from knowledge of the ion-ion RDF alone. Using the model RDFs in Effective Potential Theory, we report the first predictions of inter-species transport coefficients of strongly coupled plasmas far from equilibrium. This work is supported by NSF Grant No. PHY-1453736, AFSOR Award No. FA9550-16-1-0221, and used XSEDE computational resources.
Numerical experiments on 2D strongly coupled complex plasmas
International Nuclear Information System (INIS)
Hou Lujing; Ivlev, A V; Thomas, H M; Morfill, G E
2010-01-01
The Brownian Dynamics simulation method is briefly reviewed at first and then applied to study some non-equilibrium phenomena in strongly coupled complex plasmas, such as heat transfer processes, shock wave excitation/propagation and particle trapping, by directly mimicking the real experiments.
Dust acoustic solitary and shock waves in strongly coupled dusty ...
Indian Academy of Sciences (India)
mal vortex-like ion distribution and strongly correlated grains in a liquid-like state and discussed about the properties of shock ... shock waves in coupled dusty plasma with Boltzmann distribution of ions. Ghosh et al have studied the effect of ... ues of parameters where the nonlinear term is zero. Also new kind of shock wave.
Weak and strong coupling equilibration in nonabelian gauge theories
Energy Technology Data Exchange (ETDEWEB)
Keegan, Liam [Physics Department, Theory Unit, CERN,CH-1211 Genève 23 (Switzerland); Kurkela, Aleksi [Physics Department, Theory Unit, CERN,CH-1211 Genève 23 (Switzerland); Faculty of Science and Technology, University of Stavanger,4036 Stavanger (Norway); Romatschke, Paul [Department of Physics, 390 UCB, University of Colorado at Boulder,Boulder, CO (United States); Center for Theory of Quantum Matter, University of Colorado,Boulder, Colorado 80309 (United States); Schee, Wilke van der [Center for Theoretical Physics, MIT,Cambridge, MA 02139 (United States); Zhu, Yan [Department of Physics, University of Jyväskyla, P.O. Box 35, FI-40014 University of Jyväskylä (Finland); Helsinki Institute of Physics,P.O. Box 64, 00014 University of Helsinki (Finland)
2016-04-06
We present a direct comparison studying equilibration through kinetic theory at weak coupling and through holography at strong coupling in the same set-up. The set-up starts with a homogeneous thermal state, which then smoothly transitions through an out-of-equilibrium phase to an expanding system undergoing boost-invariant flow. This first apples-to-apples comparison of equilibration provides a benchmark for similar equilibration processes in heavy-ion collisions, where the equilibration mechanism is still under debate. We find that results at weak and strong coupling can be smoothly connected by simple, empirical power-laws for the viscosity, equilibration time and entropy production of the system.
Weak and strong coupling equilibration in nonabelian gauge theories
Keegan, Liam; Romatschke, Paul; van der Schee, Wilke; Zhu, Yan
2016-01-01
We present a direct comparison studying equilibration through kinetic theory at weak coupling and through holography at strong coupling in the same set-up. The set-up starts with a homogeneous thermal state, which then smoothly transitions through an out-of-equilibrium phase to an expanding system undergoing boost-invariant flow. This first apples-to-apples comparison of equilibration provides a benchmark for similar equilibration processes in heavy-ion collisions, where the equilibration mechanism is still under debate. We find that results at weak and strong coupling can be smoothly connected by simple, empirical power-laws for the viscosity, equilibration time and entropy production of the system.
Equilibration and hydrodynamics at strong and weak coupling
van der Schee, Wilke
2017-11-01
We give an updated overview of both weak and strong coupling methods to describe the approach to a plasma described by viscous hydrodynamics, a process now called hydrodynamisation. At weak coupling the very first moments after a heavy ion collision is described by the colour-glass condensate framework, but quickly thereafter the mean free path is long enough for kinetic theory to become applicable. Recent simulations indicate thermalization in a time t ∼ 40(η / s) 4 / 3 / T [L. Keegan, A. Kurkela, P. Romatschke, W. van der Schee, Y. Zhu, Weak and strong coupling equilibration in nonabelian gauge theories, JHEP 04 (2016) 031. arxiv:arXiv:1512.05347, doi:10.1007/JHEP04(2016)031], with T the temperature at that time and η / s the shear viscosity divided by the entropy density. At (infinitely) strong coupling it is possible to mimic heavy ion collisions by using holography, which leads to a dual description of colliding gravitational shock waves. The plasma formed hydrodynamises within a time of 0.41/T recent extension found corrections to this result for finite values of the coupling, when η / s is bigger than the canonical value of 1/4π, which leads to t ∼ (0.41 + 1.6 (η / s - 1 / 4 π)) / T [S. Grozdanov, W. van der Schee, Coupling constant corrections in holographic heavy ion collisions, arxiv:arXiv:1610.08976]. Future improvements include the inclusion of the effects of the running coupling constant in QCD.
Mamo, Kiminad A.
2013-08-01
We calculate the DC conductivity tensor of strongly coupled = 4 super-Yang-Mills (SYM) plasma in a presence of a strong external magnetic field B ≫ T 2 by using its gravity dual and employing both the RG flow approach and membrane paradigm which give the same results. We find that, since the magnetic field B induces anisotropy in the plasma, different components of the DC conductivity tensor have different magnitudes depending on whether its components are in the direction of the magnetic field B. In particular, we find that a component of the DC conductivity tensor in the direction of the magnetic field B increases linearly with B while the other components (which are not in the direction of the magnetic field B) are independent of it. These results are consistent with the lattice computations of the DC conductivity tensor of the QCD plasma in an external magnetic field B. Using the DC conductivity tensor, we calculate the soft or low-frequency thermal photon and dilepton production rates of the strongly coupled = 4 SYM plasma in the presence of the strong external magnetic field B ≫ T 2. We find that the strong magnetic field B enhances both the thermal photon and dilepton production rates of the strongly coupled = 4 SYM plasma in a qualitative agreement with the experimentally observed enhancements at the heavy-ion collision experiments.
Hydrodynamics of strongly coupled gauge theories from gravity
International Nuclear Information System (INIS)
Benincasa, P.
2007-01-01
In this talk we review some recent developments in the analysis of gauge theories from a holographic perspective. We focus on the transport properties of strongly coupled gauge theories. In particular, we discuss the results for two specific non-conformal models: the N=2* supersymmetric SU(N c ) Yang-Mills theory and the Sakai-Sugimoto model. Finally, we discuss the hydrodynamic picture for the N=4SU(N c ) SYM theory when the leading correction in the inverse 't Hooft coupling is taken into account
Superconducting proximity effect in the strong-coupling limit
International Nuclear Information System (INIS)
Wilvert, W.
1975-01-01
A generalization of the theory of the superconducting proximity effect is presented which takes into account strong-coupling in the superconductors. The results are found to agree with a model of weak-coupled superconductors with differing Debye frequencies which are in proximity. It is found that logarithmic averaging of phonon frequencies is an improvement on the original McMillan theory (1968). Comparison of the theory with data on thin films and on eutectic alloys is found to give good agreement. 19 references
From strong to ultrastrong coupling in circuit QED architectures
Energy Technology Data Exchange (ETDEWEB)
Niemczyk, Thomas
2011-08-10
The field of cavity quantum electrodynamics (cavity QED) studies the interaction between light and matter on a fundamental level: a single atom interacts with a single photon. If the atom-photon coupling is larger than any dissipative effects, the system enters the strong-coupling limit. A peculiarity of this regime is the possibility to form coherent superpositions of light and matter excitations - a kind of 'molecule' consisting of an atomic and a photonic contribution. The novel research field of circuit QED extends cavity QED concepts to solid-state based system. Here, a superconducting quantum bit is coupled to an on-chip superconducting one-dimensional waveguide resonator. Owing to the small mode-volume of the resonant cavity, the large dipole moment of the 'artificial atom' and the enormous engineering potential inherent to superconducting quantum circuits, remarkable atom-photon coupling strengths can be realized. This thesis describes the theoretical framework, the development of fabrication techniques and the implementation of experimental characterization techniques for superconducting quantum circuits for circuit QED applications. In particular, we study the interaction between superconducting flux quantum bits and high-quality coplanar waveguide resonators in the strong-coupling limit. Furthermore, we report on the first experimental realization of a circuit QED system operating in the ultrastrong-coupling regime, where the atom-photon coupling rate reaches a considerable fraction of the relevant system frequencies. In these experiments we could observe phenomena that can not be explained within the renowned Jaynes-Cummings model. (orig.)
QCD and strongly coupled gauge theories: challenges and perspectives
Energy Technology Data Exchange (ETDEWEB)
Brambilla, N.; Vairo, A. [Technische Universitaet Muenchen, Physik Department, Garching (Germany); Eidelman, S. [SB RAS, Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Foka, P. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Gardner, S. [University of Kentucky, Department of Physics and Astronomy, Lexington, KY (United States); Kronfeld, A.S. [Fermi National Accelerator Laboratory, Theoretical Physics Department, Batavia, IL (United States); Alford, M.G.; Schwenzer, K. [Washington University, Department of Physics, St Louis, MO (United States); Alkofer, R. [University of Graz, Graz (Austria); Butenschoen, M. [University of Vienna, Faculty of Physics, Wien (Austria); Cohen, T.D. [University of Maryland, Maryland Center for Fundamental Physics and Department of Physics, College Park, MD (United States); Erdmenger, J. [Max-Planck-Institute for Physics, Munich (Germany); Fabbietti, L. [Technische Universitaet Muenchen, Excellence Cluster ' ' Origin and Structure of the Universe' ' , Garching (Germany); Faber, M.; Hoellwieser, R. [Technische Universitaet Wien, Atominstitut, Vienna (Austria); Goity, J.L. [Hampton University, Hampton, VA (United States); Jefferson Laboratory, Newport News, VA (United States); Ketzer, B. [Technische Universitaet Muenchen, Physik Department, Garching (Germany); Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik, Bonn (Germany); Lin, H.W. [University of Washington, Department of Physics, Seattle, WA (United States); Llanes-Estrada, F.J. [Universidad Complutense de Madrid, Department Fisica Teorica I, Madrid (Spain); Meyer, H.B.; Wittig, H.; Hippel, G.M. von [Johannes Gutenberg-Universitaet Mainz, PRISMA Cluster of Excellence, Institut fuer Kernphysik and Helmholtz Institut Mainz, Mainz (Germany); Pakhlov, P.; Polikarpov, M.I. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Moscow Institute for Physics and Technology, Dolgoprudny (Russian Federation); Pallante, E.; Papadodimas, K. [University of Groningen, Centre for Theoretical Physics, Groningen (Netherlands); Sazdjian, H. [Universite Paris-Sud, Institut de Physique Nucleaire CNRS/IN2P3, Orsay (France); Schmitt, A. [Technische Universitaet Wien, Institut fuer Theoretische Physik, Vienna (Austria); Snow, W.M. [Indiana University, Center for Exploration of Energy and Matter and Department of Physics, Bloomington, IN (United States); Vogt, R. [Lawrence Livermore National Laboratory, Physics Division, Livermore, CA (United States); University of California, Physics Department, Davis, CA (United States); Vuorinen, A. [University of Helsinki, Department of Physics and Helsinki Institute of Physics, Helsinki (Finland); Arnold, P. [University of Virginia, Department of Physics, Charlottesville, VA (United States); Christakoglou, P. [NIKHEF, Amsterdam (Netherlands); Di Nezza, P. [Istituto Nazionale di Fisica Nucleare (INFN), Frascati (Italy); Fodor, Z. [Wuppertal University, Wuppertal (Germany); Eoetvoes University, Budapest (Hungary); Forschungszentrum Juelich, Juelich (Germany); Garcia i Tormo, X. [Universitaet Bern, Albert Einstein Center for Fundamental Physics, Institut fuer Theoretische Physik, Bern (Switzerland); Janik, M.A. [Warsaw University of Technology, Faculty of Physics, Warsaw (Poland); Kalweit, A. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Keane, D. [Kent State University, Department of Physics, Kent, OH (United States); Kiritsis, E. [University of Crete, Crete Center for Theoretical Physics, Department of Physics, Heraklion (Greece); Universite Paris Diderot, Laboratoire APC, Sorbonne Paris-Cite (France); CERN, Theory Group, Physics Department, Geneva 23 (Switzerland); Mischke, A. [Utrecht University, Faculty of Science, Utrecht (Netherlands); Mizuk, R. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Moscow Physical Engineering Institute, Moscow (Russian Federation); Odyniec, G. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Pich, A. [Universitat de Valencia, CSIC, IFIC, Valencia (Spain); Pittau, R. [Universidad de Granada, Departamento de Fisica Teorica y del Cosmos y CAFPE, Granada (Spain); Qiu, J.W. [Brookhaven National Laboratory, Physics Department, Upton, NY (United States); Stony Brook University, C.N. Yang Institute for Theoretical Physics and Department of Physics and Astronomy, Stony Brook, NY (United States); Ricciardi, G. [Universita degli Studi di Napoli Federico II, Dipartimento di Fisica, Napoli (Italy); INFN, Napoli (Italy); Salgado, C.A. [Universidade de Santiago de Compostela, Departamento de Fisica de Particulas y IGFAE, Galicia (ES); Stefanis, N.G. [Ruhr-Universitaet Bochum, Institut fuer Theoretische Physik II, Bochum (DE); Zakharov, V.I. [Max-Planck-Institute for Physics, Munich (DE); Institute of Theoretical and Experimental Physics, Moscow (RU); Moscow Institute for Physics and Technology, Dolgoprudny (RU); Far Eastern Federal University, School of Biomedicine, Vladivostok (RU)
2014-10-15
We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments. (orig.)
Strongly coupled gauge theories: What can lattice calculations teach us?
CERN. Geneva
2015-01-01
Electroweak symmetry breaking and the dynamical origin of the Higgs boson are central questions today. Strongly coupled systems predicting the Higgs boson as a bound state of a new gauge-fermion interaction are candidates to describe beyond Standard Model physics. The phenomenologically viable models are strongly coupled, near the conformal boundary, requiring non-perturbative studies to reveal their properties. Lattice studies show that many of the beyond-Standard Model candidates have a relatively light isosinglet scalar state that is well separated from the rest of the spectrum. When the scale is set via the vev of electroweak symmetry breaking, a 2 TeV vector resonance appears to be a general feature of many of these models with several other resonances that are not much heavier.
Measurement of the strong coupling constant using τ decays
Buskulic, D.; Decamp, D.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Mours, B.; Pietrzyk, B.; Alemany, R.; Ariztizabal, F.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Gaitan, V.; Garrido, Ll.; Mattison, T.; Pacheco, A.; Padilla, C.; Pascual, A.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Maggi, M.; Natali, S.; Nuzzo, S.; Quattromini, M.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Chai, Y.; Hu, H.; Huang, D.; Huang, X.; Lin, J.; Wang, T.; Xie, Y.; Xu, D.; Xu, R.; Zhang, J.; Zhang, L.; Zhao, W.; Bauerdick, L. A. T.; Blucher, E.; Bonvicini, G.; Boudreau, J.; Casper, D.; Drevermann, H.; Forty, R. W.; Ganis, G.; Gay, C.; Hagelberg, R.; Harvey, J.; Haywood, S.; Hilgart, J.; Jacobsen, R.; Jost, B.; Knobloch, J.; Lehraus, I.; Lohse, T.; Lusiani, A.; Martinez, M.; Mato, P.; Meinhard, H.; Minten, A.; Miotto, A.; Miquel, R.; Moser, H.-G.; Palazzi, P.; Perlas, J. A.; Pusztaszeri, J.-F.; Ranjard, F.; Redlinger, G.; Rolandi, L.; Rothberg, J.; Ruan, T.; Saich, M.; Schlatter, D.; Schmelling, M.; Sefkow, F.; Tejessy, W.; Wachsmuth, H.; Wiedenmann, W.; Wildish, T.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Badaud, F.; Bardadin-Otwinowska, M.; El Fellous, R.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Prulhière, F.; Saadi, F.; Fearnley, T.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Møllerud, R.; Nilsson, B. S.; Efthymiopoulos, I.; Kyriakis, A.; Simopoulou, E.; Vayaki, A.; Zachariadou, K.; Badier, J.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Fouque, G.; Orteu, S.; Rougé, A.; Rumpf, M.; Tanaka, R.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Veitch, E.; Moneta, L.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Ikeda, M.; Lannutti, J.; Levinthal, D.; Mermikides, M.; Sawyer, L.; Wasserbaech, S.; Antonelli, A.; Baldini, R.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; D'Ettorre-Piazzoli, B.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Picchi, P.; Colrain, P.; Ten Have, I.; Lynch, J. G.; Maitland, W.; Morton, W. T.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Smith, M. G.; Thompson, A. S.; Turnbull, R. M.; Brandl, B.; Braun, O.; Geweniger, C.; Hanke, P.; Hepp, V.; Kluge, E. E.; Maumary, Y.; Putzer, A.; Rensch, B.; Stahl, A.; Tittel, K.; Wunsch, M.; Belk, A. T.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Cattaneo, M.; Colling, D. J.; Dornan, P. J.; Dugeay, S.; Greene, A. M.; Hassard, J. F.; Lieske, N. M.; Nash, J.; Payne, D. G.; Phillips, M. J.; Sedgbeer, J. K.; Tomalin, I. R.; Wright, A. G.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Brodbeck, T. J.; Finch, A. J.; Foster, F.; Hughes, G.; Jackson, D.; Keemer, N. R.; Nuttall, M.; Patel, A.; Sloan, T.; Snow, S. W.; Whelan, E. P.; Kleinknecht, K.; Raab, J.; Renk, B.; Sander, H.-G.; Schmidt, H.; Steeg, F.; Walther, S. M.; Wanke, R.; Wolf, B.; Aubert, J.-J.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Carr, J.; Coyle, P.; Drinkard, J.; Etienne, F.; Nicod, D.; Papalexiou, S.; Payre, P.; Roos, L.; Rousseau, D.; Schwemling, P.; Talby, M.; Adlung, S.; Assmann, R.; Bauer, C.; Blum, W.; Brown, D.; Cattaneo, P.; Dehning, B.; Dietl, H.; Dydak, F.; Frank, M.; Halley, A. W.; Lauber, J.; Lütjens, G.; Lutz, G.; Männer, W.; Richter, R.; Rotscheidt, H.; Schröder, J.; Schwarz, A. S.; Settles, R.; Seywerd, H.; Stierlin, U.; Stiegler, U.; Denis, R. St.; Wolf, G.; Boucrot, J.; Callot, O.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Jaffe, D. E.; Janot, P.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Zhang, Z.; Abbaneo, D.; Bagliesi, G.; Batignani, G.; Bosisio, L.; Bottigli, U.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Dell'Orso, R.; Ferrante, I.; Fidecaro, F.; Foà, L.; Focardi, E.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Mannelli, E. B.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Vannini, C.; Venturi, A.; Verdini, P. G.; Walsh, J.; Betteridge, A. P.; Carter, J. M.; Green, M. G.; March, P. V.; Mir, Ll. M.; Medcalf, T.; Quazi, I. S.; Strong, J. A.; West, L. R.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Edwards, M.; Fisher, S. M.; Jones, T. J.; Norton, P. R.; Salmon, D. P.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Duarte, H.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Perrier, F.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Si Mohand, D.; Vallage, B.; Johnson, R. P.; Litke, A. M.; Taylor, G.; Wear, J.; Ashman, J. G.; Babbage, W.; Booth, C. N.; Buttar, C.; Carney, R. E.; Cartwright, S.; Combley, F.; Hatfield, F.; Thompson, L. F.; Barberio, E.; Böhrer, A.; Brandt, S.; Cowan, G.; Grupen, C.; Lutters, G.; Rivera, F.; Schäfer, U.; Smolik, L.; Della Marina, R.; Giannini, G.; Gobbo, B.; Ragusa, F.; Bellantoni, L.; Chen, W.; Cinabro, D.; Conway, J. S.; Cowen, D. F.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; Grahl, J.; Harton, J. L.; Jared, R. C.; Leclaire, B. W.; Lishka, C.; Pan, Y. B.; Pater, J. R.; Saadi, Y.; Sharma, V.; Schmitt, M.; Shi, Z. H.; Walsh, A. M.; Weber, F. V.; Lan Wu, Sau; Wu, X.; Zheng, M.; Zobernig, G.; Aleph Collaboration
1993-06-01
The strong coupling constant is determined from the leptonic branching ratios, the lifetime, and the invariant mass distribution of the hadronic final state of the τ lepton, using data accumulated at LEP with the ALEPH detector. The strong coupling constant measurement, αs( mτ2) = 0.330±0.046, evolved to the Z mass yields αs( MZ2) = 0.188±0.005. The error includes experimental and theoretical uncertainties, the latter evaluated in the framework of the Shifman, Vainshtein and Zakharov (SVZ) approach. The method allows the non-perturbative contribution to the hadronic decay rate to be determined to be 0.3±0.5%.
Jet quenching parameters in strongly coupled nonconformal gauge theories
International Nuclear Information System (INIS)
Buchel, Alex
2006-01-01
Recently Liu, Rajagopal, and Wiedemann (LRW) [H. Liu, K. Rajagopal, and U. A. Wiedemann, hep-ph/0605178.] proposed a first principle, nonperturbative quantum field theoretic definition of 'jet quenching parameter' q-circumflex used in models of medium-induced radiative parton energy loss in nucleus-nucleus collisions at RHIC. Relating q-circumflex to a short-distance behavior of a certain lightlike Wilson loop, they used gauge theory-string theory correspondence to evaluate q-circumflex for the strongly coupled N=4 SU(N c ) gauge theory plasma. We generalize analysis of LRW to strongly coupled nonconformal gauge theory plasma. We find that a jet quenching parameter is gauge theory specific (not universal). Furthermore, it appears its value increases as the number of effective adjoint degrees of freedom of a gauge theory plasma increases
Equation of state of strongly coupled plasma mixtures
International Nuclear Information System (INIS)
DeWitt, H.E.
1984-01-01
Thermodynamic properties of strongly coupled (high density) plasmas of mixtures of light elements have been obtained by Monte Carlo simulations. For an assumed uniform charge background the equation of state of ionic mixtures is a simple extension of the one-component plasma EOS. More realistic electron screening effects are treated in linear response theory and with an appropriate electron dielectric function. Results have been obtained for the ionic pair distribution functions, and for the electric microfield distribution
Correlated Fluctuations in Strongly Coupled Binary Networks Beyond Equilibrium
Directory of Open Access Journals (Sweden)
David Dahmen
2016-08-01
Full Text Available Randomly coupled Ising spins constitute the classical model of collective phenomena in disordered systems, with applications covering glassy magnetism and frustration, combinatorial optimization, protein folding, stock market dynamics, and social dynamics. The phase diagram of these systems is obtained in the thermodynamic limit by averaging over the quenched randomness of the couplings. However, many applications require the statistics of activity for a single realization of the possibly asymmetric couplings in finite-sized networks. Examples include reconstruction of couplings from the observed dynamics, representation of probability distributions for sampling-based inference, and learning in the central nervous system based on the dynamic and correlation-dependent modification of synaptic connections. The systematic cumulant expansion for kinetic binary (Ising threshold units with strong, random, and asymmetric couplings presented here goes beyond mean-field theory and is applicable outside thermodynamic equilibrium; a system of approximate nonlinear equations predicts average activities and pairwise covariances in quantitative agreement with full simulations down to hundreds of units. The linearized theory yields an expansion of the correlation and response functions in collective eigenmodes, leads to an efficient algorithm solving the inverse problem, and shows that correlations are invariant under scaling of the interaction strengths.
Strongly Coupled Models with a Higgs-like Boson*
Directory of Open Access Journals (Sweden)
Pich Antonio
2013-11-01
Full Text Available Considering the one-loop calculation of the oblique S and T parameters, we have presented a study of the viability of strongly-coupled scenarios of electroweak symmetry breaking with a light Higgs-like boson. The calculation has been done by using an effective Lagrangian, being short-distance constraints and dispersive relations the main ingredients of the estimation. Contrary to a widely spread believe, we have demonstrated that strongly coupled electroweak models with massive resonances are not in conflict with experimentalconstraints on these parameters and the recently observed Higgs-like resonance. So there is room for these models, but they are stringently constrained. The vector and axial-vector states should be heavy enough (with masses above the TeV scale, the mass splitting between them is highly preferred to be small and the Higgs-like scalar should have a WW coupling close to the Standard Model one. It is important to stress that these conclusions do not depend critically on the inclusion of the second Weinberg sum rule.
Strong Local-Nonlocal Coupling for Integrated Fracture Modeling
Energy Technology Data Exchange (ETDEWEB)
Littlewood, David John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Silling, Stewart A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mitchell, John A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Seleson, Pablo D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bond, Stephen D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Parks, Michael L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Turner, Daniel Z. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Burnett, Damon J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ostien, Jakob [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Gunzburger, Max [Florida State Univ., Tallahassee, FL (United States)
2015-09-01
Peridynamics, a nonlocal extension of continuum mechanics, is unique in its ability to capture pervasive material failure. Its use in the majority of system-level analyses carried out at Sandia, however, is severely limited, due in large part to computational expense and the challenge posed by the imposition of nonlocal boundary conditions. Combined analyses in which peridynamics is em- ployed only in regions susceptible to material failure are therefore highly desirable, yet available coupling strategies have remained severely limited. This report is a summary of the Laboratory Directed Research and Development (LDRD) project "Strong Local-Nonlocal Coupling for Inte- grated Fracture Modeling," completed within the Computing and Information Sciences (CIS) In- vestment Area at Sandia National Laboratories. A number of challenges inherent to coupling local and nonlocal models are addressed. A primary result is the extension of peridynamics to facilitate a variable nonlocal length scale. This approach, termed the peridynamic partial stress, can greatly reduce the mathematical incompatibility between local and nonlocal equations through reduction of the peridynamic horizon in the vicinity of a model interface. A second result is the formulation of a blending-based coupling approach that may be applied either as the primary coupling strategy, or in combination with the peridynamic partial stress. This blending-based approach is distinct from general blending methods, such as the Arlequin approach, in that it is specific to the coupling of peridynamics and classical continuum mechanics. Facilitating the coupling of peridynamics and classical continuum mechanics has also required innovations aimed directly at peridynamic models. Specifically, the properties of peridynamic constitutive models near domain boundaries and shortcomings in available discretization strategies have been addressed. The results are a class of position-aware peridynamic constitutive laws for
Transport Theory for Plasmas that are Strongly Magnetized and Strongly Coupled
Baalrud, Scott; Daligault, Jerome
2016-10-01
Plasmas with components that are magnetized, strongly coupled, or both arise in a variety of frontier plasma physics experiments including magnetized dusty plasmas, nonneutral plasmas, magnetized ICF concepts, as well as from self-generated fields in ICF. Here, a species is considered strongly magnetized if the gyroradius is smaller than the spatial scale over which Coulomb interactions occur. A theory for transport properties is described that treats a wide range of both coupling and magnetization strengths. The approach is based on an extension of the recent effective potential transport theory to include a strong magnetic field. The underlying kinetic theory is based on an extension of the Boltzmann equation to include a strong magnetic field in the dynamics of binary scattering events. Corresponding magnetohydrodynamic equations are derived by solving the kinetic equation using a Chapman-Enskog like spectral method. Results are compared with classical molecular dynamics simulations of self-diffusion of the one component plasmas, and with simulations of parallel to perpendicular temperature equilibration of an initially anisotropic distribution. This material is based upon work supported by AFOSR Award FA9550-16-1-0221 and DOE OFES Award DE-SC0016159.
Enhancement of low-temperature thermometry by strong coupling
Correa, Luis A.; Perarnau-Llobet, Martí; Hovhannisyan, Karen V.; Hernández-Santana, Senaida; Mehboudi, Mohammad; Sanpera, Anna
2017-12-01
We consider the problem of estimating the temperature T of a very cold equilibrium sample. The temperature estimates are drawn from measurements performed on a quantum Brownian probe strongly coupled to it. We model this scenario by resorting to the canonical Caldeira-Leggett Hamiltonian and find analytically the exact stationary state of the probe for arbitrary coupling strength. In general, the probe does not reach thermal equilibrium with the sample, due to their nonperturbative interaction. We argue that this is advantageous for low-temperature thermometry, as we show in our model that (i) the thermometric precision at low T can be significantly enhanced by strengthening the probe-sampling coupling, (ii) the variance of a suitable quadrature of our Brownian thermometer can yield temperature estimates with nearly minimal statistical uncertainty, and (iii) the spectral density of the probe-sample coupling may be engineered to further improve thermometric performance. These observations may find applications in practical nanoscale thermometry at low temperatures—a regime which is particularly relevant to quantum technologies.
Strongly coupled dusty plasmas: crystals, liquids, clusters and waves
International Nuclear Information System (INIS)
Jeng-Mei Liu; Wen-Tau Juan; Ju-Wang Hsu; Zen-Hong Huang; Lin I
1999-01-01
The dusty plasma is a system that consists of many strongly-charged fine dust particles suspended in a plasma background. The slow dynamics and strong coupling due to the large mass and charges lead to the formation of highly-ordered dust crystal structures suspended in the plasma background, which can be directly observed. The dusty plasma forms a link to the area of condensed matter physics for the study of many interesting microscopic phenomena from order to disorder. In this paper, we introduce the special properties of this system from the viewpoint of conventional plasma physics, then we briefly review past works on the structure and dynamical behaviour from the highly-ordered state, through the melting and liquid states with associated vortex-type excitation and anomalous diffusion, to the state with self-organized macroscopic dust waves after losing microscopic order. The first observation of strongly-coupled dust Coulomb clusters with small numbers of particles from a few to a few hundred, which resemble classical atoms, is also demonstrated. (author)
Strongly Coupled Chameleons and the Neutronic Quantum Bouncer
International Nuclear Information System (INIS)
Brax, Philippe; Pignol, Guillaume
2011-01-01
We consider the potential detection of chameleons using bouncing ultracold neutrons. We show that the presence of a chameleon field over a planar plate would alter the energy levels of ultracold neutrons in the terrestrial gravitational field. When chameleons are strongly coupled to nuclear matter, β > or approx. 10 8 , we find that the shift in energy levels would be detectable with the forthcoming GRANIT experiment, where a sensitivity of the order of 1% of a peV is expected. We also find that an extremely large coupling β > or approx. 10 11 would lead to new bound states at a distance of order 2 μm, which is already ruled out by previous Grenoble experiments. The resulting bound, β 11 , is already 3 orders of magnitude better than the upper bound, β 14 , from precision tests of atomic spectra.
Strong coupling QCD at finite baryon-number density
International Nuclear Information System (INIS)
Karsch, F.; Muetter, K.H.
1989-01-01
We present a new representation of the partition function for strong-coupling QCD which is suitable also for finite baryon-number-density simulations. This enables us to study the phase structure in the canonical formulation (with fixed baryon number B) as well as the grand canonical one (with fixed chemical potential μ). We find a clear signal for a first-order chiral phase transition at μ c a=0.63. The critical baryon-number density n c a 3 =0.045 is only slightly higher than the density of nuclear matter. (orig.)
Topological Zak phase in strongly coupled LC circuits
Goren, Tal; Plekhanov, Kirill; Appas, Félicien; Le Hur, Karyn
2018-01-01
We show the emergence of topological Bogoliubov bosonic excitations in the relatively strong coupling limit of an LC (inductance-capacitance) one-dimensional quantum circuit. This dimerized chain model reveals a Z2 local symmetry as a result of the counter-rotating wave (pairing) terms. The topology is protected by the sublattice symmetry, represented by an antiunitary transformation. We present a method to measure the winding of the topological Zak phase across the Brillouin zone by a reflection measurement of (microwave) light. Our method probes bulk quantities and can be implemented even in small systems. We study the robustness of edge modes toward disorder.
Black hole thermodynamics from calculations in strongly coupled gauge theory.
Kabat, D; Lifschytz, G; Lowe, D A
2001-02-19
We develop an approximation scheme for the quantum mechanics of N D0-branes at finite temperature in the 't Hooft large- N limit. The entropy of the quantum mechanics calculated using this approximation agrees well with the Bekenstein-Hawking entropy of a ten-dimensional nonextremal black hole with 0-brane charge. This result is in accordance with the duality conjectured by Itzhaki, Maldacena, Sonnenschein, and Yankielowicz [Phys. Rev. D 58, 046004 (1998)]. Our approximation scheme provides a model for the density matrix which describes a black hole in the strongly coupled quantum mechanics.
Strongly coupled stimulated Brillouin amplification in pump-ionizing plasma
Peng, H.; Wu, Z. H.; Zuo, Y. L.; Zhou, K. N.; Wang, X. D.; Li, Q.; Zhu, H. Y.; Su, J. Q.
2018-02-01
Laser amplification based on strongly coupled stimulated Brillouin scattering in plasma is investigated. The pump and seed are at the same wavelength of 800 nm and the same duration of 3.5 ps, but with a different intensity. The plasma is produced by the front part of the pump via tunnel ionization from hydrogen. The hydrogen is fully ionized to eliminate small-scale density fluctuations in the plasma, so the transmission level of the seed is enhanced to 22%, and a relative amplification factor of 6 is obtained.
Strong-coupling approach to nematicity in the cuprates
Orth, Peter Philipp; Jeevanesan, Bhilahari; Schmalian, Joerg; Fernandes, Rafael
The underdoped cuprate superconductor YBa2Cu3O7-δ is known to exhibit an electronic nematic phase in proximity to antiferromagnetism. While nematicity sets in at large temperatures of T ~ 150 K, static spin density wave order only emerges at much lower temperatures. The magnetic response shows a strong in-plane anisotropy, displaying incommensurate Bragg peaks along one of the crystalline directions and a commensurate peak along the other one. Such an anisotropy persists even in the absence of long-range magnetic order at higher temperatures, marking the onset of nematic order. Here we theoretically investigate this situation using a strong-coupling method that takes into account both the localized Cu spins and the holes doped into the oxygen orbitals. We derive an effective spin Hamiltonian and show that charge fluctuations promote an enhancement of the nematic susceptibility near the antiferromagnetic transition temperature.
Double perovskites with strong spin-orbit coupling
Cook, Ashley M.
We first present theoretical analysis of powder inelastic neutron scattering experiments in Ba2FeReO6 performed by our experimental collaborators. Ba2FeReO6, a member of the double perovskite family of materials, exhibits half-metallic behavior and high Curie temperatures Tc, making it of interest for spintronics applications. To interpret the experimental data, we develop a local moment model, which incorporates the interaction of Fe spins with spin-orbital locked magnetic moments on Re, and show that it captures the experimental observations. We then develop a tight-binding model of the double perovskite Ba 2FeReO6, a room temperature ferrimagnet with correlated and spin-orbit coupled Re t2g electrons moving in the background of Fe moments stabilized by Hund's coupling. We show that for such 3d/5d double perovskites, strong correlations on the 5d-element (Re) are essential in driving a half-metallic ground state. Incorporating both strong spin-orbit coupling and the Hubbard repulsion on Re leads to a band structure consistent with ab initio calculations. The uncovered interplay of strong correlations and spin-orbit coupling lends partial support to our previous work, which used a local moment description to capture the spin wave dispersion found in neutron scattering measurements. We then adapt this tight-binding model to study {111}-grown bilayers of half-metallic double perovskites such as Sr2FeMoO6. The combination of spin-orbit coupling, inter-orbital hybridization and symmetry-allowed trigonal distortion leads to a rich phase diagram with tunable ferromagnetic order, topological C= +/-1, +/-2 Chern bands, and a C = +/-2 quantum anomalous Hall insulator regime. We have also performed theoretical analysis of inelastic neutron scattering (INS) experiments to investigate the magnetic excitations in the weakly distorted face-centered-cubic (fcc) iridate double perovskites La2ZnIrO 6 and La2MgIrO6. Models with dominant Kitaev exchange seem to most naturally
Strong wave/mean-flow coupling in baroclinic acoustic streaming
Chini, Greg; Michel, Guillaume
2017-11-01
Recently, Chini et al. demonstrated the potential for large-amplitude acoustic streaming in compressible channel flows subjected to strong background cross-channel density variations. In contrast with classic Rayleigh streaming, standing acoustic waves of O (ɛ) amplitude acquire vorticity owing to baroclinic torques acting throughout the domain rather than via viscous torques acting in Stokes boundary layers. More significantly, these baroclinically-driven streaming flows have a magnitude that also is O (ɛ) , i.e. comparable to that of the sound waves. In the present study, the consequent potential for fully two-way coupling between the waves and streaming flows is investigated using a novel WKBJ analysis. The analysis confirms that the wave-driven streaming flows are sufficiently strong to modify the background density gradient, thereby modifying the leading-order acoustic wave structure. Simulations of the wave/mean-flow system enabled by the WKBJ analysis are performed to illustrate the nature of the two-way coupling, which contrasts sharply with classic Rayleigh streaming, for which the waves can first be determined and the streaming flows subsequently computed.
Strongly Coupled Magnetic and Electronic Transitions in Multivalent Strontium Cobaltites.
Lee, J H; Choi, Woo Seok; Jeen, H; Lee, H-J; Seo, J H; Nam, J; Yeom, M S; Lee, H N
2017-11-22
The topotactic phase transition in SrCoO x (x = 2.5-3.0) makes it possible to reversibly transit between the two distinct phases, i.e. the brownmillerite SrCoO 2.5 that is a room-temperature antiferromagnetic insulator (AFM-I) and the perovskite SrCoO 3 that is a ferromagnetic metal (FM-M), owing to their multiple valence states. For the intermediate x values, the two distinct phases are expected to strongly compete with each other. With oxidation of SrCoO 2.5 , however, it has been conjectured that the magnetic transition is decoupled to the electronic phase transition, i.e., the AFM-to-FM transition occurs before the insulator-to-metal transition (IMT), which is still controversial. Here, we bridge the gap between the two-phase transitions by density-functional theory calculations combined with optical spectroscopy. We confirm that the IMT actually occurs concomitantly with the FM transition near the oxygen content x = 2.75. Strong charge-spin coupling drives the concurrent IMT and AFM-to-FM transition, which fosters the near room-T magnetic transition characteristic. Ultimately, our study demonstrates that SrCoO x is an intriguingly rare candidate for inducing coupled magnetic and electronic transition via fast and reversible redox reactions.
Equilibrium statistical mechanics of strongly coupled plasmas by numerical simulation
International Nuclear Information System (INIS)
DeWitt, H.E.
1977-01-01
Numerical experiments using the Monte Carlo method have led to systematic and accurate results for the thermodynamic properties of strongly coupled one-component plasmas and mixtures of two nuclear components. These talks are intended to summarize the results of Monte Carlo simulations from Paris and from Livermore. Simple analytic expressions for the equation of state and other thermodynamic functions have been obtained in which there is a clear distinction between a lattice-like static portion and a thermal portion. The thermal energy for the one-component plasma has a simple power dependence on temperature, (kT)/sup 3 / 4 /, that is identical to Monte Carlo results obtained for strongly coupled fluids governed by repulsive l/r/sup n/ potentials. For two-component plasmas the ion-sphere model is shown to accurately represent the static portion of the energy. Electron screening is included in the Monte Carlo simulations using linear response theory and the Lindhard dielectric function. Free energy expressions have been constructed for one and two component plasmas that allow easy computation of all thermodynamic functions
Pair correlation functions of strongly coupled two-temperature plasma
Shaffer, Nathaniel R.; Tiwari, Sanat Kumar; Baalrud, Scott D.
2017-09-01
Using molecular dynamics simulations, we perform the first direct tests of three proposed models for the pair correlation functions of strongly coupled plasmas with species of unequal temperature. The models are all extensions of the Ornstein-Zernike/hypernetted-chain theory used to good success for equilibrium plasmas. Each theory is evaluated at several coupling strengths, temperature ratios, and mass ratios for a model plasma in which the electrons are positively charged. We show that the model proposed by Seuferling et al. [Phys. Rev. A 40, 323 (1989)] agrees well with molecular dynamics over a wide range of mass and temperature ratios, as well as over a range of coupling strength similar to that of the equilibrium hypernetted-chain (HNC) theory. The SVT model also correctly predicts the strength of interspecies correlations and exhibits physically reasonable long-wavelength limits of the static structure factors. Comparisons of the SVT model with the Yukawa one-component plasma (YOCP) model are used to show that ion-ion pair correlations are well described by the YOCP model up to Γe≈1 , beyond which it rapidly breaks down.
Strongly coupled inorganic/nanocarbon hybrid materials for advanced electrocatalysis.
Liang, Yongye; Li, Yanguang; Wang, Hailiang; Dai, Hongjie
2013-02-13
Electrochemical systems, such as fuel cell and water splitting devices, represent some of the most efficient and environmentally friendly technologies for energy conversion and storage. Electrocatalysts play key roles in the chemical processes but often limit the performance of the entire systems due to insufficient activity, lifetime, or high cost. It has been a long-standing challenge to develop efficient and durable electrocatalysts at low cost. In this Perspective, we present our recent efforts in developing strongly coupled inorganic/nanocarbon hybrid materials to improve the electrocatalytic activities and stability of inorganic metal oxides, hydroxides, sulfides, and metal-nitrogen complexes. The hybrid materials are synthesized by direct nucleation, growth, and anchoring of inorganic nanomaterials on the functional groups of oxidized nanocarbon substrates including graphene and carbon nanotubes. This approach affords strong chemical attachment and electrical coupling between the electrocatalytic nanoparticles and nanocarbon, leading to nonprecious metal-based electrocatalysts with improved activity and durability for the oxygen reduction reaction for fuel cells and chlor-alkali catalysis, oxygen evolution reaction, and hydrogen evolution reaction. X-ray absorption near-edge structure and scanning transmission electron microscopy are employed to characterize the hybrids materials and reveal the coupling effects between inorganic nanomaterials and nanocarbon substrates. Z-contrast imaging and electron energy loss spectroscopy at single atom level are performed to investigate the nature of catalytic sites on ultrathin graphene sheets. Nanocarbon-based hybrid materials may present new opportunities for the development of electrocatalysts meeting the requirements of activity, durability, and cost for large-scale electrochemical applications.
The strong coupling constant of QCD with four flavors
Energy Technology Data Exchange (ETDEWEB)
Tekin, Fatih
2010-11-01
In this thesis we study the theory of strong interaction Quantum Chromodynamics on a space-time lattice (lattice QCD) with four flavors of dynamical fermions by numerical simulations. In the early days of lattice QCD, only pure gauge field simulations were accessible to the computational facilities and the effects of quark polarization were neglected. The so-called fermion determinant in the path integral was set to one (quenched approximation). The reason for this approximation was mainly the limitation of computational power because the inclusion of the fermion determinant required an enormous numerical effort. However, for full QCD simulations the virtual quark loops had to be taken into account and the development of new machines and new algorithmic techniques made the so-called dynamical simulations with at least two flavors possible. In recent years, different collaborations studied lattice QCD with dynamical fermions. In our project we study lattice QCD with four degenerated flavors of O(a) improved Wilson quarks in the Schroedinger functional scheme and calculate the energy dependence of the strong coupling constant. For this purpose, we determine the O(a) improvement coefficient c{sub sw} with four flavors and use this result to calculate the step scaling function of QCD with four flavors which describes the scale evolution of the running coupling. Using a recursive finite-size technique, the {lambda} parameter is determined in units of a technical scale L{sub max} which is an unambiguously defined length in the hadronic regime. The coupling {alpha}{sub SF} of QCD in the so-called Schroedinger functional scheme is calculated over a wide range of energies non-perturbatively and compared with 2-loop and 3-loop perturbation theory as well as with the non-perturbative result for only two flavors. (orig.)
Perspective: Coulomb fluids--weak coupling, strong coupling, in between and beyond.
Naji, Ali; Kanduc, Matej; Forsman, Jan; Podgornik, Rudolf
2013-10-21
We present a personal view on the current state of statistical mechanics of Coulomb fluids with special emphasis on the interactions between macromolecular surfaces, concentrating on the weak and the strong coupling limits. Both are introduced for a (primitive) counterion-only system in the presence of macroscopic, uniformly charged boundaries, where they can be derived systematically. Later we show how this formalism can be generalized to the cases with additional characteristic length scales that introduce new coupling parameters into the problem. These cases most notably include asymmetric ionic mixtures with mono- and multivalent ions that couple differently to charged surfaces, ions with internal charge (multipolar) structure and finite static polarizability, where weak and strong coupling limits can be constructed by analogy with the counterion-only case and lead to important new insights into their properties that cannot be derived by any other means.
Mathematical structure of Rabi oscillations in the strong coupling regime
International Nuclear Information System (INIS)
Fujii, Kazuyuki
2003-01-01
In this paper, we generalize the Jaynes-Cummings Hamiltonian by making use of some operators based on Lie algebras su(1, 1) and su(2), and study a mathematical structure of Rabi floppings of these models in the strong coupling regime. We show that Rabi frequencies are given by matrix elements of generalized coherent operators (Fujii K 2002 Preprint quant-ph/0202081) under the rotating-wave approximation. In the first half, we make a general review of coherent operators and generalized coherent ones based on Lie algebras su(1, 1) and su(2). In the latter half, we carry out a detailed examination of Frasca (Frasca M 2001 Preprint quant-ph/0111134) and generalize his method, and moreover present some related problems. We also apply our results to the construction of controlled unitary gates in quantum computation. Lastly, we make a brief comment on application to holonomic quantum computation
Charge pumping in strongly coupled molecular quantum dots
Haughian, Patrick; Yap, Han Hoe; Gong, Jiangbin; Schmidt, Thomas L.
2017-11-01
The interaction between electrons and the vibrational degrees of freedom of a molecular quantum dot can lead to an exponential suppression of the conductance, an effect which is commonly termed Franck-Condon blockade. Here, we investigate this effect in a quantum dot driven by time-periodic gate voltages and tunneling amplitudes using nonequilibrium Green's functions and a Floquet expansion. Building on previous results showing that driving can lift the Franck-Condon blockade, we investigate driving protocols which can be used to pump charge across the quantum dot. In particular, we show that due to the strongly coupled nature of the system, the pump current at resonance is an exponential function of the drive strength.
On the flavor problem in strongly coupled theories
Energy Technology Data Exchange (ETDEWEB)
Bauer, Martin
2012-11-28
This thesis is on the flavor problem of Randall Sundrum models and their strongly coupled dual theories. These models are particularly well motivated extensions of the Standard Model, because they simultaneously address the gauge hierarchy problem and the hierarchies in the quark masses and mixings. In order to put this into context, special attention is given to concepts underlying the theories which can explain the hierarchy problem and the flavor structure of the Standard Model (SM). The AdS/CFT duality is introduced and its implications for the Randall Sundrum model with fermions in the bulk and general bulk gauge groups is investigated. It is shown that the different terms in the general 5D propagator of a bulk gauge field can be related to the corresponding diagrams of the strongly coupled dual, which allows for a deeper understanding of the origin of flavor changing neutral currents generated by the exchange of the Kaluza Klein excitations of these bulk fields. In the numerical analysis, different observables which are sensitive to corrections from the tree-level exchange of these resonances will be presented on the basis of updated experimental data from the Tevatron and LHC experiments. This includes electroweak precision observables, namely corrections to the S and T parameters followed by corrections to the Zb anti b vertex, flavor changing observables with flavor changes at one vertex, viz. B(B{sub d}{yields}{mu}{sup +}{mu}{sup -}) and B(B{sub s}{yields}{mu}{sup +}{mu}{sup -}), and two vertices, viz. S{sub {psi}{phi}} and vertical stroke {epsilon}{sub K} vertical stroke, as well as bounds from direct detection experiments. The analysis will show that all of these bounds can be brought in agreement with a new physics scale {Lambda}{sub NP} in the TeV range, except for the CP violating quantity vertical stroke {epsilon}{sub K} vertical stroke, which requires {Lambda}{sub NP}=O(10) TeV in the absence of fine-tuning. The numerous modifications of the
Quantum Thermodynamics in Strong Coupling: Heat Transport and Refrigeration
Directory of Open Access Journals (Sweden)
Gil Katz
2016-05-01
Full Text Available The performance characteristics of a heat rectifier and a heat pump are studied in a non-Markovian framework. The device is constructed from a molecule connected to a hot and cold reservoir. The heat baths are modelled using the stochastic surrogate Hamiltonian method. The molecule is modelled by an asymmetric double-well potential. Each well is semi-locally connected to a heat bath composed of spins. The dynamics are driven by a combined system–bath Hamiltonian. The temperature of the baths is regulated by a secondary spin bath composed of identical spins in thermal equilibrium. A random swap operation exchange spins between the primary and secondary baths. The combined system is studied in various system–bath coupling strengths. In all cases, the average heat current always flows from the hot towards the cold bath in accordance with the second law of thermodynamics. The asymmetry of the double well generates a rectifying effect, meaning that when the left and right baths are exchanged the heat current follows the hot-to-cold direction. The heat current is larger when the high frequency is coupled to the hot bath. Adding an external driving field can reverse the transport direction. Such a refrigeration effect is modelled by a periodic driving field in resonance with the frequency difference of the two potential wells. A minimal driving amplitude is required to overcome the heat leak effect. In the strong driving regime the cooling power is non-monotonic with the system–bath coupling.
Peptide-microgel interactions in the strong coupling regime.
Hansson, Per; Bysell, Helena; Månsson, Ronja; Malmsten, Martin
2012-09-06
The interaction between lightly cross-linked poly(acrylic acid) microgels and oppositely charged peptides was investigated as a function of peptide length, charge density, pH, and salt concentration, with emphasis on the strong coupling regime at high charge contrast. By micromanipulator-assisted light microscopy, the equilibrium volume response of single microgel particles upon oligolysine and oligo(lysine/alanine) absorption could be monitored in a controlled fashion. Results show that microgel deswelling, caused by peptide binding and network neutralization, increases with peptide length (3 attraction between the network chains is described using an exponential force law, and the network elasticity by the inverse Langevin theory. The model was used to calculate the composition of microgels in contact with reservoir solutions of peptides and simple electrolytes. At high electrostatic coupling, the calculated swelling curves were found to display first-order phase transition behavior. The model was demonstrated to capture pH- and electrolyte-dependent microgel swelling, as well as effects of peptide length and charge density on microgel deswelling. The analysis demonstrated that the peptide charge (length), rather than the peptide charge density, determines microgel deswelling. Furthermore, a transition between continuous and discrete network collapse was identified, consistent with experimental results in the present investigations, as well as with results from the literature on microgel deswelling caused by multivalent cations.
Thermalization and confinement in strongly coupled gauge theories
Directory of Open Access Journals (Sweden)
Ishii Takaaki
2016-01-01
Full Text Available Quantum field theories of strongly interacting matter sometimes have a useful holographic description in terms of the variables of a gravitational theory in higher dimensions. This duality maps time dependent physics in the gauge theory to time dependent solutions of the Einstein equations in the gravity theory. In order to better understand the process by which “real world” theories such as QCD behave out of thermodynamic equilibrium, we study time dependent perturbations to states in a model of a confining, strongly coupled gauge theory via holography. Operationally, this involves solving a set of non-linear Einstein equations supplemented with specific time dependent boundary conditions. The resulting solutions allow one to comment on the timescale by which the perturbed states thermalize, as well as to quantify the properties of the final state as a function of the perturbation parameters. We comment on the influence of the dual gauge theory’s confinement scale on these results, as well as the appearance of a previously anticipated universal scaling regime in the “abrupt quench” limit.
Holographic Floquet states I: a strongly coupled Weyl semimetal
Hashimoto, Koji; Kinoshita, Shunichiro; Murata, Keiju; Oka, Takashi
2017-05-01
Floquet states can be realized in quantum systems driven by continuous time-periodic perturbations. It is known that a state known as the Floquet Weyl semimetal can be realized when free Dirac fermions are placed in a rotating electric field. What will happen if strong interaction is introduced to this system? Will the interaction wash out the characteristic features of Weyl semimetals such as the Hall response? Is there a steady state and what is its thermodynamic behavior? We answer these questions using AdS/CFT correspondence in the N = 2 supersymmetric massless QCD in a rotating electric field in the large N c limit realizing the first example of a "holographic Floquet state". In this limit, gluons not only mediate interaction, but also act as an energy reservoir and stabilize the nonequilibrium steady state (NESS). We obtain the electric current induced by a rotating electric field: in the high frequency region, the Ohm's law is satisfied, while we recover the DC nonlinear conductivity at low frequency, which was obtained holographically in a previous work. The thermodynamic properties of the NESS, e.g., fluctuation-dissipation relation, is characterized by the effective Hawking temperature that is defined from the effective horizon giving a holographic meaning to the "periodic thermodynamic" concept. In addition to the strong (pump) rotating electric field, we apply an additional weak (probe) electric field in the spirit of the pump-probe experiments done in condensed matter experiments. Weak DC and AC probe analysis in the background rotating electric field shows Hall currents as a linear response, therefore the Hall response of Floquet Weyl semimetals survives at the strong coupling limit. We also find frequency mixed response currents, i.e., a heterodyning effect, characteristic to periodically driven Floquet systems.
Large mass hierarchies from strongly-coupled dynamics
Athenodorou, Andreas; Bennett, Ed; Bergner, Georg; Elander, Daniel; Lin, C.-J. David; Lucini, Biagio; Piai, Maurizio
2016-06-01
Besides the Higgs particle discovered in 2012, with mass 125 GeV, recent LHC data show tentative signals for new resonances in diboson as well as diphoton searches at high center-of-mass energies (2 TeV and 750 GeV, respectively). If these signals are confirmed (or other new resonances are discovered at the TeV scale), the large hierarchies between masses of new bosons require a dynamical explanation. Motivated by these tentative signals of new physics, we investigate the theoretical possibility that large hierarchies in the masses of glueballs could arise dynamically in new strongly-coupled gauge theories extending the standard model of particle physics. We study lattice data on non-Abelian gauge theories in the (near-)conformal regime as well as a simple toy model in the context of gauge/gravity dualities. We focus our attention on the ratio R between the mass of the lightest spin-2 and spin-0 resonances, that for technical reasons is a particularly convenient and clean observable to study. For models in which (non-perturbative) large anomalous dimensions arise dynamically, we show indications that this mass ratio can be large, with R>5. Moreover,our results suggest that R might be related to universal properties of the IR fixed point. Our findings provide an interesting step towards understanding large mass ratios in the non-perturbative regime of quantum field theories with (near) IR conformal behaviour.
Stochastic and Macroscopic Thermodynamics of Strongly Coupled Systems
Directory of Open Access Journals (Sweden)
Christopher Jarzynski
2017-01-01
Full Text Available We develop a thermodynamic framework that describes a classical system of interest S that is strongly coupled to its thermal environment E. Within this framework, seven key thermodynamic quantities—internal energy, entropy, volume, enthalpy, Gibbs free energy, heat, and work—are defined microscopically. These quantities obey thermodynamic relations including both the first and second law, and they satisfy nonequilibrium fluctuation theorems. We additionally impose a macroscopic consistency condition: When S is large, the quantities defined within our framework scale up to their macroscopic counterparts. By satisfying this condition, we demonstrate that a unifying framework can be developed, which encompasses both stochastic thermodynamics at one end, and macroscopic thermodynamics at the other. A central element in our approach is a thermodynamic definition of the volume of the system of interest, which converges to the usual geometric definition when S is large. We also sketch an alternative framework that satisfies the same consistency conditions. The dynamics of the system and environment are modeled using Hamilton’s equations in the full phase space.
Effect of random charge fluctuation on strongly coupled dusty Plasma
Issaad, M.; Rouiguia, L.; Djebli, M.
2008-09-01
Modeling the interaction between particles is an open issue in dusty plasma. We dealt with strongly coupled dust particles in two dimensional confined system. For small number of clusters, we investigate the effect of random charge fluctuation on background configuration. The study is conducted for a short rang as well as a long rang potential interaction. Numerical simulation is performed using Monte-Carlo simulation in the presence of parabolic confinement and at low temperature. We have studied the background configurations for a dust particles with constant charge and in the presence of random charge fluctuation due to the discrete nature of charge carriers. The latter is studied for a positively charged dust when the dominant charging process is due to photo-emission from the dust surface. It is found, for small classical cluster consisting of small number of particles, short rang potential gives the same result as long rang one. It is also found that the random charge fluctuation affect the background configurations.
Weak-coupling superconductivity in a strongly correlated iron pnictide.
Charnukha, A; Post, K W; Thirupathaiah, S; Pröpper, D; Wurmehl, S; Roslova, M; Morozov, I; Büchner, B; Yaresko, A N; Boris, A V; Borisenko, S V; Basov, D N
2016-01-05
Iron-based superconductors have been found to exhibit an intimate interplay of orbital, spin, and lattice degrees of freedom, dramatically affecting their low-energy electronic properties, including superconductivity. Albeit the precise pairing mechanism remains unidentified, several candidate interactions have been suggested to mediate the superconducting pairing, both in the orbital and in the spin channel. Here, we employ optical spectroscopy (OS), angle-resolved photoemission spectroscopy (ARPES), ab initio band-structure, and Eliashberg calculations to show that nearly optimally doped NaFe0.978Co0.022As exhibits some of the strongest orbitally selective electronic correlations in the family of iron pnictides. Unexpectedly, we find that the mass enhancement of itinerant charge carriers in the strongly correlated band is dramatically reduced near the Γ point and attribute this effect to orbital mixing induced by pronounced spin-orbit coupling. Embracing the true band structure allows us to describe all low-energy electronic properties obtained in our experiments with remarkable consistency and demonstrate that superconductivity in this material is rather weak and mediated by spin fluctuations.
Strongly coupled gauge theories: What can lattice calculations teach us?
Hasenfratz, A.; Brower, R. C.; Rebbi, C.; Weinberg, E.; Witzel, O.
2017-12-01
The dynamical origin of electroweak symmetry breaking is an open question with many possible theoretical explanations. Strongly coupled systems predicting the Higgs boson as a bound state of a new gauge-fermion interaction form one class of candidate models. Due to increased statistics, LHC run II will further constrain the phenomenologically viable models in the near future. In the meanwhile it is important to understand the general properties and specific features of the different competing models. In this work we discuss many-flavor gauge-fermion systems that contain both massless (light) and massive fermions. The former provide Goldstone bosons and trigger electroweak symmetry breaking, while the latter indirectly influence the infrared dynamics. Numerical results reveal that such systems can exhibit a light 0++ isosinglet scalar, well separated from the rest of the spectrum. Further, when we set the scale via the vev of electroweak symmetry breaking, we predict a 2 TeV vector resonance which could be a generic feature of SU(3) gauge theories.
Ising models of strongly coupled biological networks with multivariate interactions
Merchan, Lina; Nemenman, Ilya
2013-03-01
Biological networks consist of a large number of variables that can be coupled by complex multivariate interactions. However, several neuroscience and cell biology experiments have reported that observed statistics of network states can be approximated surprisingly well by maximum entropy models that constrain correlations only within pairs of variables. We would like to verify if this reduction in complexity results from intricacies of biological organization, or if it is a more general attribute of these networks. We generate random networks with p-spin (p > 2) interactions, with N spins and M interaction terms. The probability distribution of the network states is then calculated and approximated with a maximum entropy model based on constraining pairwise spin correlations. Depending on the M/N ratio and the strength of the interaction terms, we observe a transition where the pairwise approximation is very good to a region where it fails. This resembles the sat-unsat transition in constraint satisfaction problems. We argue that the pairwise model works when the number of highly probable states is small. We argue that many biological systems must operate in a strongly constrained regime, and hence we expect the pairwise approximation to be accurate for a wide class of problems. This research has been partially supported by the James S McDonnell Foundation grant No.220020321.
NEON VISUALIZATION ENVIRONMENT
2017-07-28
over the HTTP REST interface. A JavaScript library for accessing the REST interface is included to further ease the development of web applications...transformation tools that would be useful to end users. Its origin in OWF widgets and the simple demonstration of the JavaScript API quickly evolved...services connected to big data stores to perform querying, filtering, and aggregation. The Neon Client was a Javascript library from which
D-brane physics. From weak to strong coupling
Energy Technology Data Exchange (ETDEWEB)
Vieira Lopes, Daniel Ordine
2013-01-10
In this thesis we discuss two aspects of branes relevant to high-energy phenomenology. First, we consider a single D6-brane wrapping a special Lagrangian cycle and the background space compactified in a Calabi-Yau orientifold the conditions needed to obtain a four-dimensional N=1 supersymmetric theory. We calculate the bosonic part of the effective action by performing a Kaluza-Klein reduction of the brane seven-dimensional action, and obtain the N=1 characteristic data. To discuss the moduli, we first fix the moduli from deformations of the background Calabi-Yau and study the D-brane deformation moduli space. We next allow for Calabi-Yau deformations, and show that the moduli space for complex structure deformations is corrected by the fields living on the D6-brane. We also calculate the scalar potential from D- and F-terms generated from brane and background configurations that would break the supersymmetry condition. We then, via Mirror Symmetry, relate the spectrum obtained in our work to the spectrum in Type IIB effective theory with D3- D5- and D7-branes, and we propose a Kaehler potential for the moduli space of brane deformations in Type IIB theories. In the second part of the thesis we discuss effects of brane intersections when the string coupling can become strong, and we work in the framework of F-theory. After reviewing the basics of F-theory constructions and a particular SU(5) model already discussed in the literature, we construct a model which contains a point of E{sub 8} singularity, and curves of E{sub 6} singularity. By explicitly resolving the space, we show that the resolution requires the introduction of higher dimensional fibers, and argue how we can circumvent this problem for the E{sub 6} curve, leading to the expected resolution that generate an E{sub 6} group, while at the E{sub 8} point we cannot make the resolution lead to an expected E{sub 8} structure.
Strong coupling of collection of emitters on hyperbolic meta-material
Biehs, Svend-Age; Xu, Chenran; Agarwal, Girish S.
2018-04-01
Recently, considerable effort has been devoted to the realization of a strong coupling regime of the radiation matter interaction in the context of an emitter at a meta surface. The strong interaction is well realized in cavity quantum electrodynamics, which also show that strong coupling is much easier to realize using a collection of emitters. Keeping this in mind, we study if emitters on a hyperbolic meta materials can yield a strong coupling regime. We show that strong coupling can be realized for densities of emitters exceeding a critical value. A way to detect strong coupling between emitters and hyperbolic metamaterials is to use the Kretschman-Raether configuration. The strong coupling appears as the splitting of the reflectivity dip. In the weak coupling regime, the dip position shifts. The shift and splitting can be used to sense active molecules at surfaces.
Strongly coupled partitioned FSI using proper orthogonal decomposition
CSIR Research Space (South Africa)
Bogaers, Alfred EJ
2012-12-01
Full Text Available that this dependence on the number of retained histories is due to a trade-off between increasingly ill-conditioned interface Jacobian, when too many histories are retained and sub-optimal coupling convergence rates due to a loss of information when histories...
Strongly coupled, low noise DC-SQUID amplifiers
Pleikies, J.
2009-01-01
The dc Superconducting Quantum Interference Device (dc-SQUID) is one of the most sensitive magnetic field sensors available. In this thesis we concentrate on its application as an amplifier. In this configuration, an input circuit of interest can be connected by means of a coupling coil. The
Strong Carrier–Phonon Coupling in Lead Halide Perovskite Nanocrystals
2017-01-01
We highlight the importance of carrier–phonon coupling in inorganic lead halide perovskite nanocrystals. The low-temperature photoluminescence (PL) spectrum of CsPbBr3 has been investigated under a nonresonant and a nonstandard, quasi-resonant excitation scheme, and phonon replicas of the main PL band have been identified as due to the Fröhlich interaction. The energy of longitudinal optical (LO) phonons has been determined from the separation of the zero phonon band and phonon replicas. We reason that the observed LO phonon coupling can only be related to an orthorhombically distorted crystal structure of the perovskite nanocrystals. Additionally, the strength of carrier–phonon coupling has been characterized using the ratio between the intensities of the first phonon replica and the zero-phonon band. PL emission from localized versus delocalized carriers has been identified as the source of the observed discrepancies between the LO phonon energy and phonon coupling strength under quasi-resonant and nonresonant excitation conditions, respectively. PMID:29019652
Strong Carrier-Phonon Coupling in Lead Halide Perovskite Nanocrystals
Iaru, Claudiu M; Geuchies, Jaco J|info:eu-repo/dai/nl/370526090; Koenraad, Paul M; Vanmaekelbergh, Daniël|info:eu-repo/dai/nl/304829137; Silov, Andrei Yu
2017-01-01
We highlight the importance of carrier-phonon coupling in inorganic lead halide perovskite nanocrystals. The low-temperature photoluminescence (PL) spectrum of CsPbBr3 has been investigated under a nonresonant and a nonstandard, quasi-resonant excitation scheme, and phonon replicas of the main PL
Modelling of strongly coupled particle growth and aggregation
International Nuclear Information System (INIS)
Gruy, F; Touboul, E
2013-01-01
The mathematical modelling of the dynamics of particle suspension is based on the population balance equation (PBE). PBE is an integro-differential equation for the population density that is a function of time t, space coordinates and internal parameters. Usually, the particle is characterized by a unique parameter, e.g. the matter volume v. PBE consists of several terms: for instance, the growth rate and the aggregation rate. So, the growth rate is a function of v and t. In classical modelling, the growth and the aggregation are independently considered, i.e. they are not coupled. However, current applications occur where the growth and the aggregation are coupled, i.e. the change of the particle volume with time is depending on its initial value v 0 , that in turn is related to an aggregation event. As a consequence, the dynamics of the suspension does not obey the classical Von Smoluchowski equation. This paper revisits this problem by proposing a new modelling by using a bivariate PBE (with two internal variables: v and v 0 ) and by solving the PBE by means of a numerical method and Monte Carlo simulations. This is applied to a physicochemical system with a simple growth law and a constant aggregation kernel.
Static and Dynamic Amplification Using Strong Mechanical Coupling
Ilyas, Saad
2016-07-28
Amplifying the signal-to-noise ratio of resonant sensors is vital toward the effort to miniaturize devices into the sub-micro and nano regimes. In this paper, we demonstrate theoretically and experimentally, amplification through mechanically coupled microbeams. The device is composed of two identical clamped-clamped beams, made of polyimide, connected at their middle through a third beam, which acts as a mechanical coupler. Each of the clamped-clamped microbeams and the coupler are designed to be actuated separately, hence providing various possibilities of actuation and sensing. The coupled resonator is driven into resonance near its first resonance mode and its dynamic behavior is explored via frequency sweeps. The results show significant amplification in the resonator amplitude when the signal is measured at the midpoint of the coupler compared with the response of the individual uncoupled beams. The static pull-in characteristics of the resonator are also studied. It is shown that the compliant mechanical coupler can serve as a low-power radio frequency switch actuated at low voltage loads. [2016-0100
Thermodynamics and instabilities of a strongly coupled anisotropic plasma
Mateos, David; Trancanelli, Diego
2011-07-01
We extend our analysis of a IIB supergravity solution dual to a spatially anisotropic finite-temperature mathcal{N} = 4 super Yang-Mills plasma. The solution is static, possesses an anisotropic horizon, and is completely regular. The full geometry can be viewed as a renormalization group flow from an AdS geometry in the ultraviolet to a Lifshitz-like geometry in the infrared. The anisotropy can be equivalently understood as resulting from a position-dependent θ-term or from a non-zero number density of dissolved D7-branes. The holographic stress tensor is conserved and anisotropic. The presence of a conformal anomaly plays an important role in the thermodynamics. The phase diagram exhibits homogeneous and inhomogeneous (i.e. mixed) phases. In some regions the homogeneous phase displays instabilities reminiscent of those of weakly coupled plasmas. We comment on similarities with QCD at finite baryon density and with the phenomenon of cavitation.
Clean HMBC: Suppression of strong-coupling induced artifacts in HMBC spectra
DEFF Research Database (Denmark)
Würtz, Peter; Permi, Perttu; Nielsen, Niels Chr.
2008-01-01
in HMBC spectra, but they have apparently been overlooked, presumably because they have been assigned to inefficiency of low-pass J filters or not noticed because of a coarse digital resolution in the spectra. Clean HMBC is the HMBC technique of choice for molecules notorious for strong coupling among......A new experiment, clean HMBC, is introduced for suppression of strong-coupling induced artifacts in HMBC spectra. The culprits of these artifacts are an inherent shortcoming of low-pass J filters in the presence of strong coupling and the 1H p pulse in the middle of the evolution period aimed...... at suppressing evolution under heteronuclear J couplings and 1H chemical shifts. A p pulse causes coherence transfer in strongly coupled spin systems and, as is well known in e.g., homonuclear J spectra, this leads to peaks that would not be there in the absence of strong coupling. Similar artifacts occur...
Strongly Coupled Magnetic and Electronic Transitions in Multivalent Strontium Cobaltites
Lee, J. H.; Choi, Woo Seok; Jeen, H.; Lee, H.-J.; Seo, J. H.; Nam, J.; Yeom, M. S.; Lee, H. N.
2017-01-01
The topotactic phase transition in SrCoO x (x = 2.5–3.0) makes it possible to reversibly transit between the two distinct phases, i.e. the brownmillerite SrCoO2.5 that is a room-temperature antiferromagnetic insulator (AFM-I) and the perovskite SrCoO3 that is a ferromagnetic metal (FM-M), owing to their multiple valence states. For the intermediate x values, the two distinct phases are expected to strongly compete with each other. With oxidation of SrCoO2.5, however, it has been conjectured t...
Inelastic electron scattering influence on the strong coupling oxide superconductors
International Nuclear Information System (INIS)
Gabovich, A.M.; Voitenko, A.I.
1995-01-01
The superconducting order parameters Δ and energy gap Δ g are calculated taking into account the pair-breaking inelastic quasiparticle scattering by thermal Bose-excitations, e.g., phonons. The treatment is self-consistent because the scattering amplitude depends on Δ. The superconducting transition for any strength of the inelastic scattering is the phase transition of the first kind and the dependences Δ (T) and Δ g (T) tend to rectangular curve that agrees well with the experiment for high-Tc oxides. On the basis of the developed theory the nuclear spin-lattice relaxation rate R s in the superconducting state is calculated. The Hebel-Slichter peak in R s (T) is shown to disappear for strong enough inelastic scattering
Thermal DBI action for the D3-brane at weak and strong coupling
DEFF Research Database (Denmark)
Grignani, Gianluca; Harmark, Troels; Marini, Andrea
2014-01-01
We study the effective action for finite-temperature D3-branes with an electromagnetic field at weak and strong coupling. We call this action the thermal DBI action. Comparing at low temperature the leading T4 correction for the thermal DBI action at weak and strong coupling we find that the 3/4 ...
Strong coupling constant extraction from high-multiplicity Z +jets observables
Johnson, Mark; Maître, Daniel
2018-03-01
We present a strong coupling constant extraction at next-to-leading order QCD accuracy using ATLAS Z +2 ,3,4 jets data. This is the first extraction using processes with a dependency on high powers of the coupling constant. We obtain values of the strong coupling constant at the Z mass compatible with the world average and with uncertainties commensurate with other next-to-leading order extractions at hadron colliders. Our most conservative result for the strong coupling constant is αS(MZ)=0.117 8-0.0043+0.0051 .
Strongly coupled dispersed two-phase flows; Ecoulements diphasiques disperses fortement couples
Energy Technology Data Exchange (ETDEWEB)
Zun, I.; Lance, M.; Ekiel-Jezewska, M.L.; Petrosyan, A.; Lecoq, N.; Anthore, R.; Bostel, F.; Feuillebois, F.; Nott, P.; Zenit, R.; Hunt, M.L.; Brennen, C.E.; Campbell, C.S.; Tong, P.; Lei, X.; Ackerson, B.J.; Asmolov, E.S.; Abade, G.; da Cunha, F.R.; Lhuillier, D.; Cartellier, A.; Ruzicka, M.C.; Drahos, J.; Thomas, N.H.; Talini, L.; Leblond, J.; Leshansky, A.M.; Lavrenteva, O.M.; Nir, A.; Teshukov, V.; Risso, F.; Ellinsen, K.; Crispel, S.; Dahlkild, A.; Vynnycky, M.; Davila, J.; Matas, J.P.; Guazelli, L.; Morris, J.; Ooms, G.; Poelma, C.; van Wijngaarden, L.; de Vries, A.; Elghobashi, S.; Huilier, D.; Peirano, E.; Minier, J.P.; Gavrilyuk, S.; Saurel, R.; Kashinsky, O.; Randin, V.; Colin, C.; Larue de Tournemine, A.; Roig, V.; Suzanne, C.; Bounhoure, C.; Brunet, Y.; Tanaka, A.T.; Noma, K.; Tsuji, Y.; Pascal-Ribot, S.; Le Gall, F.; Aliseda, A.; Hainaux, F.; Lasheras, J.; Didwania, A.; Costa, A.; Vallerin, W.; Mudde, R.F.; Van Den Akker, H.E.A.; Jaumouillie, P.; Larrarte, F.; Burgisser, A.; Bergantz, G.; Necker, F.; Hartel, C.; Kleiser, L.; Meiburg, E.; Michallet, H.; Mory, M.; Hutter, M.; Markov, A.A.; Dumoulin, F.X.; Suard, S.; Borghi, R.; Hong, M.; Hopfinger, E.; Laforgia, A.; Lawrence, C.J.; Hewitt, G.F.; Osiptsov, A.N.; Tsirkunov, Yu. M.; Volkov, A.N.
2003-07-01
This document gathers the abstracts of the Euromech 421 colloquium about strongly coupled dispersed two-phase flows. Behaviors specifically due to the two-phase character of the flow have been categorized as: suspensions, particle-induced agitation, microstructure and screening mechanisms; hydrodynamic interactions, dispersion and phase distribution; turbulence modulation by particles, droplets or bubbles in dense systems; collective effects in dispersed two-phase flows, clustering and phase distribution; large-scale instabilities and gravity driven dispersed flows; strongly coupled two-phase flows involving reacting flows or phase change. Topic l: suspensions particle-induced agitation microstructure and screening mechanisms hydrodynamic interactions between two very close spheres; normal stresses in sheared suspensions; a critical look at the rheological experiments of R.A. Bagnold; non-equilibrium particle configuration in sedimentation; unsteady screening of the long-range hydrodynamic interactions of settling particles; computer simulations of hydrodynamic interactions among a large collection of sedimenting poly-disperse particles; velocity fluctuations in a dilute suspension of rigid spheres sedimenting between vertical plates: the role of boundaries; screening and induced-agitation in dilute uniform bubbly flows at small and moderate particle Reynolds numbers: some experimental results. Topic 2: hydrodynamic interactions, dispersion and phase distribution: hydrodynamic interactions in a bubble array; A 'NMR scattering technique' for the determination of the structure in a dispersion of non-brownian settling particles; segregation and clustering during thermo-capillary migration of bubbles; kinetic modelling of bubbly flows; velocity fluctuations in a homogeneous dilute dispersion of high-Reynolds-number rising bubbles; an attempt to simulate screening effects at moderate particle Reynolds numbers using an hybrid formulation; modelling the two
Strong Helioseismic Constraints on Weakly-Coupled Plasmas
Nayfonov, Alan
The extraordinary accuracy of helioseismic data allows detailed theoretical studies of solar plasmas. The necessity to produce solar models matching the experimental results in accuracy imposes strong constrains on the equations of state of solar plasmas. Several discrepancies between the experimental data and models have been successfully identified as the signatures of various non-ideal phenomena. Of a particular interest are questions of the position of the energy levels and the continuum edge and of the effect of the excited states in the solar plasma. Calculations of energy level and continuum shifts, based on the Green function formalism, appeared recently in the literature. These results have been used to examine effects of the shifts on the thermodynamic quantities. A comparison with helioseismic data has shown that the calculations based on lower-level approximations, such as the static screening in the effective two-particle wave equation, agree very well with the experimental data. However, the case of full dynamic screening produces thermodynamic quantities inconsistent with observations. The study of the effect of different internal partition functions on a complete set of thermodynamic quantities has revealed the signature of the excited states in the MHD (Mihalas, Hummer, Dappen) equation of state. The presence of exited states causes a characteristic 'wiggle' in the thermodynamic quantities due to the density-dependent occupation probabilities. This effect is absent if the ACTEX (ACTivity EXpansion) equation of state is used. The wiggle has been found to be most prominent in the quantities sensitive to density. The size of this excited states effect is well within the observational power of helioseismology, and very recent inversion analyses of helioseismic data seem to indicate the presence of the wiggle in the sun. This has a potential importance for the helioseismic determination of the helium abundance of the sun.
Cirtog, M; Asselin, P; Soulard, P; Tremblay, B; Madebène, B; Alikhani, M E; Georges, R; Moudens, A; Goubet, M; Huet, T R; Pirali, O; Roy, P
2011-03-31
A series of hydrogen bonded complexes involving oxirane and water molecules have been studied. In this paper we report on the vibrational study of the oxirane-water complex (CH(2))(2)O-H(2)O. Neon matrix experiments and ab initio anharmonic vibrational calculations have been performed, providing a consistent set of vibrational frequencies and anharmonic coupling constants. The implementation of a new large flow supersonic jet coupled to the Bruker IFS 125 HR spectrometer at the infrared AILES beamline of the French synchrotron SOLEIL (Jet-AILES) enabled us to record first jet-cooled Fourier transform infrared spectra of oxirane-water complexes at different resolutions down to 0.2 cm(-1). Rovibrational parameters and a lower bound of the predissociation lifetime of 25 ps for the v(OH)(b) = 1 state have been derived from the rovibrational analysis of the ν(OH)(b) band contour recorded at respective rotational temperatures of 12 K (Jet-AILES) and 35 K (LADIR jet).
Electrically tunable single-dot nanocavities in the weak and strong coupling regimes
DEFF Research Database (Denmark)
Laucht, Arne; Hofbauer, Felix; Angele, Jacob
2008-01-01
We report the design, fabrication and optical investigation of electrically tunable single quantum dot - photonic crystal defect nanocavities [1] operating in both the weak and strong coupling regimes of the light matter interaction. Unlike previous studies, where the dot-cavity spectral detuning...... of the emitted photons from a single-dot nanocavity in the weak and strong coupling regimes. New information is obtained on the nature of the dot-cavity coupling in the weak coupling regime and electrical control of zero dimensional polaritons is demonstrated for the first time. Vacuum Rabi splittings up to 2g...... electrical readout of the strongly coupled dot-cavity system using photocurrent methods will be discussed. This work is financially supported by the DFG via SFB 631 and by the German Excellence Initiative via the “Nanosystems Initiative Munich (NIM)”....
Ratio of bulk to shear viscosity in a quasigluon plasma: from weak to strong coupling
Bluhm, M; Redlich, K
2012-01-01
The ratio of bulk to shear viscosity is expected to exhibit a different behaviour in weakly and in strongly coupled systems. This can be expressed by the dependence of the ratio on the squared sound velocity. In the high temperature QCD plasma at small running coupling, the viscosity ratio is uniquely determined by a quadratic dependence on the conformality measure, whereas in certain strongly coupled and nearly conformal theories this dependence is linear. Employing an effective kinetic theory of quasiparticle excitations with medium-modified dispersion relation, we analyze the ratio of bulk to shear viscosity of the gluon plasma. We show that in this approach the viscosity ratio comprises both dependencies found by means of weak coupling perturbative and strong coupling holographic techniques.
Ricketts, David S.; Chabalko, Matthew J.; Hillenius, Andrew
2013-02-01
In this work, we show experimentally that wireless power transfer (WPT) using strongly coupled magnetic resonance (SCMR) and traditional induction are equivalent. We demonstrate that for a given coil separation, and to within 4%, strongly coupled magnetic resonance and traditional induction produce the same theoretical efficiency of wireless power transfer versus distance. Moreover, we show that the difference between traditional induction and strongly coupled magnetic resonance is in the implementation of the impedance matching network where strongly coupled magnetic resonance uses the mini-loop impedance match. The mini-loop impedance mach provides a low-loss, high-ratio impedance transformation that makes it desirable for longer distance wireless power transfer, where large impedance transformations are needed to maximize power transfer.
Spin-orbit-induced strong coupling of a single spin to a nanomechanical resonator
DEFF Research Database (Denmark)
Pályi, András; Struck, P R; Rudner, Mark
2012-01-01
We theoretically investigate the deflection-induced coupling of an electron spin to vibrational motion due to spin-orbit coupling in suspended carbon nanotube quantum dots. Our estimates indicate that, with current capabilities, a quantum dot with an odd number of electrons can serve....... The strong intrinsic spin-mechanical coupling allows for detection, as well as manipulation of the spin qubit, and may yield enhanced performance of nanotubes in sensing applications....
Extending the reach of strong-coupling: an iterative technique for Hamiltonian lattice models
International Nuclear Information System (INIS)
Alberty, J.; Greensite, J.; Patkos, A.
1983-12-01
The authors propose an iterative method for doing lattice strong-coupling-like calculations in a range of medium to weak couplings. The method is a modified Lanczos scheme, with greatly improved convergence properties. The technique is tested on the Mathieu equation and on a Hamiltonian finite-chain XY model, with excellent results. (Auth.)
Bose condensation in an attractive fermion gas: From weak to strong coupling superconductivity
International Nuclear Information System (INIS)
Nozieres, P.; Schmitt-Rink, S.
1985-01-01
We consider a gas of fermions interacting via an attractive potential. We study the ground state of that system and calculate the critical temperature for the onset of superconductivity as a function of the coupling strength. We compare the behavior of continuum and lattice models and show that the evolution from weak to strong coupling superconductivity is smooth
Zhou, Ning; Yuan, Meng; Gao, Yuhan; Li, Dongsheng; Yang, Deren
2016-04-26
Strong coupling between semiconductor excitons and localized surface plasmons (LSPs) giving rise to hybridized plexciton states in which energy is coherently and reversibly exchanged between the components is vital, especially in the area of quantum information processing from fundamental and practical points of view. Here, in photoluminescence spectra, rather than from common extinction or reflection measurements, we report on the direct observation of Rabi splitting of approximately 160 meV as an indication of strong coupling between excited states of CdSe/ZnS quantum dots (QDs) and LSP modes of silver nanoshells under nonresonant nanosecond pulsed laser excitation at room temperature. The strong coupling manifests itself as an anticrossing-like behavior of the two newly formed polaritons when tuning the silver nanoshell plasmon energies across the exciton line of the QDs. Further analysis substantiates the essentiality of high pump energy and collective strong coupling of many QDs with the radiative dipole mode of the metallic nanoparticles for the realization of strong coupling. Our finding opens up interesting directions for the investigation of strong coupling between LSPs and excitons from the perspective of radiative recombination under easily accessible experimental conditions.
Strong coupling and polariton lasing in Te based microcavities embedding (Cd,Zn)Te quantum wells
Energy Technology Data Exchange (ETDEWEB)
Rousset, J.-G., E-mail: j-g.rousset@fuw.edu.pl; Piętka, B.; Król, M.; Mirek, R.; Lekenta, K.; Szczytko, J.; Borysiuk, J.; Suffczyński, J.; Kazimierczuk, T.; Goryca, M.; Smoleński, T.; Kossacki, P.; Nawrocki, M.; Pacuski, W. [Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, PL-02-093 Warszawa (Poland)
2015-11-16
We report on properties of an optical microcavity based on (Cd,Zn,Mg)Te layers and embedding (Cd,Zn)Te quantum wells. The key point of the structure design is the lattice matching of the whole structure to MgTe, which eliminates the internal strain and allows one to embed an arbitrary number of unstrained quantum wells in the microcavity. We evidence the strong light-matter coupling regime already for the structure containing a single quantum well. Embedding four unstrained quantum wells results in further enhancement of the exciton-photon coupling and the polariton lasing in the strong coupling regime.
Energy Technology Data Exchange (ETDEWEB)
Hensen, Matthias [Institut; Heilpern, Tal [Center; Gray, Stephen K. [Center; Pfeiffer, Walter [Fakultät
2017-10-12
Establishing strong coupling between spatially separated and thus selectively addressable quantum emitters is a key ingredient to complex quantum optical schemes in future technologies. Insofar as many plasmonic nanostructures are concerned, however, the energy transfer and mutual interaction strength between distant quantum emitters can fail to provide strong coupling. Here, based on mode hybridization, the longevity and waveguide character of an elliptical plasmon cavity are combined with intense and highly localized field modes of suitably designed nanoantennas. Based on FDTD simulations a quantum emitter-plasmon coupling strength hg = 16.7 meV is reached while simultaneously keeping a small plasmon resonance line width h gamma(s) = 33 meV. This facilitates strong coupling, and quantum dynamical simulations reveal an oscillatory exchange of excited state population arid a notable degree of entanglement between the quantum emitters spatially separated by 1.8 mu m, i.e., about twice the operating wavelength.
Analog quantum simulation of the Rabi model in the ultra-strong coupling regime.
Braumüller, Jochen; Marthaler, Michael; Schneider, Andre; Stehli, Alexander; Rotzinger, Hannes; Weides, Martin; Ustinov, Alexey V
2017-10-03
The quantum Rabi model describes the fundamental mechanism of light-matter interaction. It consists of a two-level atom or qubit coupled to a quantized harmonic mode via a transversal interaction. In the weak coupling regime, it reduces to the well-known Jaynes-Cummings model by applying a rotating wave approximation. The rotating wave approximation breaks down in the ultra-strong coupling regime, where the effective coupling strength g is comparable to the energy ω of the bosonic mode, and remarkable features in the system dynamics are revealed. Here we demonstrate an analog quantum simulation of an effective quantum Rabi model in the ultra-strong coupling regime, achieving a relative coupling ratio of g/ω ~ 0.6. The quantum hardware of the simulator is a superconducting circuit embedded in a cQED setup. We observe fast and periodic quantum state collapses and revivals of the initial qubit state, being the most distinct signature of the synthesized model.An analog quantum simulation scheme has been explored with a quantum hardware based on a superconducting circuit. Here the authors investigate the time evolution of the quantum Rabi model at ultra-strong coupling conditions, which is synthesized by slowing down the system dynamics in an effective frame.
Room-temperature cavity quantum electrodynamics with strongly coupled Dicke states
Breeze, Jonathan D.; Salvadori, Enrico; Sathian, Juna; Alford, Neil McN.; Kay, Christopher W. M.
2017-09-01
The strong coupling regime is essential for efficient transfer of excitations between states in different quantum systems on timescales shorter than their lifetimes. The coupling of single spins to microwave photons is very weak but can be enhanced by increasing the local density of states by reducing the magnetic mode volume of the cavity. In practice, it is difficult to achieve both small cavity mode volume and low cavity decay rate, so superconducting metals are often employed at cryogenic temperatures. For an ensembles of N spins, the spin-photon coupling can be enhanced by √{N } through collective spin excitations known as Dicke states. For sufficiently large N the collective spin-photon coupling can exceed both the spin decoherence and cavity decay rates, making the strong-coupling regime accessible. Here we demonstrate strong coupling and cavity quantum electrodynamics in a solid-state system at room-temperature. We generate an inverted spin-ensemble with N 1015 by photo-exciting pentacene molecules into spin-triplet states with spin dephasing time T2* 3 μs. When coupled to a 1.45 GHz TE01δ mode supported by a high Purcell factor strontium titanate dielectric cavity (Vm 0.25 cm3, Q 8,500), we observe Rabi oscillations in the microwave emission from collective Dicke states and a 1.8 MHz normal-mode splitting of the resultant collective spin-photon polariton. We also observe a cavity protection effect at the onset of the strong-coupling regime which decreases the polariton decay rate as the collective coupling increases.
International Nuclear Information System (INIS)
Radtke, R.J.; Norman, M.R.
1994-01-01
Recent angle-resolved photoemission (ARPES) experiments have indicated that the electronic dispersion in some of the cuprates possesses an extended saddle point near the Fermi level which gives rise to a density of states that diverges like a power law instead of the weaker logarithmic divergence usually considered. We investigate whether this strong singularity can give rise to high transition temperatures by computing the critical temperature T c and isotope effect coefficient α within a strong-coupling Eliashberg theory which accounts for the full energy variation of the density of states. Using band structures extracted from ARPES measurements, we demonstrate that, while the weak-coupling solutions suggest a strong influence of the strength of the Van Hove singularity on T c and α, strong-coupling solutions show less sensitivity to the singularity strength and do not support the hypothesis that band-structure effects alone can account for either the large T c 's or the different T c 's within the copper oxide family. This conclusion is supported when our results are plotted as a function of the physically relevant self-consistent coupling constant, which shows universal behavior at very strong coupling
Room temperature strong light-matter coupling in three dimensional terahertz meta-atoms
Energy Technology Data Exchange (ETDEWEB)
Paulillo, B., E-mail: bruno.paulillo@u-psud.fr; Manceau, J.-M., E-mail: jean-michel.manceau@u-psud.fr; Colombelli, R., E-mail: raffaele.colombelli@u-psud.fr [Institut d' Electronique Fondamentale, Univ. Paris Sud, UMR8622 CNRS, 91405 Orsay (France); Li, L. H.; Davies, A. G.; Linfield, E. H. [School of Electronic and Electrical Engineering, University of Leeds, Woodhouse Lane, Leeds LS2 9JT (United Kingdom)
2016-03-07
We demonstrate strong light-matter coupling in three dimensional terahertz meta-atoms at room temperature. The intersubband transition of semiconductor quantum wells with a parabolic energy potential is strongly coupled to the confined circuital mode of three-dimensional split-ring metal-semiconductor-metal resonators that have an extreme sub-wavelength volume (λ/10). The frequency of these lumped-element resonators is controlled by the size and shape of the external antenna, while the interaction volume remains constant. This allows the resonance frequency to be swept across the intersubband transition and the anti-crossing characteristic of the strong light-matter coupling regime to be observed. The Rabi splitting, which is twice the Rabi frequency (2Ω{sub Rabi}), amounts to 20% of the bare transition at room temperature, and it increases to 28% at low-temperature.
The Bekenstein bound in strongly coupled O(N) scalar field theory
International Nuclear Information System (INIS)
Magalhaes, T. Santos; Svaiter, N.F.; Menezes, G.
2009-09-01
We discuss the O(N) self-interacting scalar field theory, in the strong-coupling regime and also in the limit of large N. Considering that the system is in thermal equilibrium with a reservoir at temperature β -1 , we assume the presence of macroscopic boundaries conning the field in a hypercube of side L. Using the strong-coupling perturbative expansion, we generalize previous results, i.e., we obtain the renormalized mean energy E and entropy S for the system in rst order of the strong-coupling perturbative expansion, presenting an analytical proof that the specific entropy also satisfies in some situations a quantum bound. When considering the low temperature behavior of the specific entropy, the sign of the renormalized zero-point energy can invalidate this quantum bound. If the renormalized zero point-energy is a positive quantity, at intermediate temperatures and in the low temperature limit, there is a quantum bound. (author)
The strong-weak coupling symmetry in 2D Φ4 field models
Directory of Open Access Journals (Sweden)
B.N.Shalaev
2005-01-01
Full Text Available It is found that the exact beta-function β(g of the continuous 2D gΦ4 model possesses two types of dual symmetries, these being the Kramers-Wannier (KW duality symmetry and the strong-weak (SW coupling symmetry f(g, or S-duality. All these transformations are explicitly constructed. The S-duality transformation f(g is shown to connect domains of weak and strong couplings, i.e. above and below g*. Basically it means that there is a tempting possibility to compute multiloop Feynman diagrams for the β-function using high-temperature lattice expansions. The regular scheme developed is found to be strongly unstable. Approximate values of the renormalized coupling constant g* found from duality symmetry equations are in an agreement with available numerical results.
Ideal gas behavior of a strongly-coupled complex (dusty) plasma
Oxtoby, Neil P.; Griffith, Elias J.; Durniak, Céline; Ralph, Jason F.; Samsonov, Dmitry
2012-01-01
In a laboratory, a two-dimensional complex (dusty) plasma consists of a low-density ionized gas containing a confined suspension of Yukawa-coupled plastic microspheres. For an initial crystal-like form, we report ideal gas behavior in this strongly coupled system during shock-wave experiments. This evidence supports the use of the ideal gas law as the equation of state for soft crystals such as those formed by dusty plasmas.
Plexcitons: The Role of Oscillator Strengths and Spectral Widths in Determining Strong Coupling
Energy Technology Data Exchange (ETDEWEB)
Thomas, Reshmi [School; Thomas, Anoop [School; Pullanchery, Saranya [School; Joseph, Linta [School; Somasundaran, Sanoop Mambully [School; Swathi, Rotti Srinivasamurthy [School; Gray, Stephen K. [Center; Thomas, K. George [School
2018-01-05
Strong coupling interactions between plasmon and exciton-based excitations have been proposed to be useful in the design of optoelectronic systems. However, the role of various optical parameters dictating the plasmon-exciton (plexciton) interactions is less understood. Herein, we propose an inequality for achieving strong coupling between plasmons and excitons through appropriate variation of their oscillator strengths and spectral widths. These aspects are found to be consistent with experiments on two sets of free-standing plexcitonic systems obtained by (i) linking fluorescein isothiocyanate on Ag nanoparticles of varying sizes through silane coupling and (ii) electrostatic binding of cyanine dyes on polystyrenesulfonate-coated Au nanorods of varying aspect ratios. Being covalently linked on Ag nanoparticles, fluorescein isothiocyanate remains in monomeric state, and its high oscillator strength and narrow spectral width enable us to approach the strong coupling limit. In contrast, in the presence of polystyrenesulfonate, monomeric forms of cyanine dyes exist in equilibrium with their aggregates: Coupling is not observed for monomers and H-aggregates whose optical parameters are unfavorable. The large aggregation number, narrow spectral width, and extremely high oscillator strength of J-aggregates of cyanines permit effective delocalization of excitons along the linear assembly of chromophores, which in turn leads to efficient coupling with the plasmons. Further, the results obtained from experiments and theoretical models are jointly employed to describe the plexcitonic states, estimate the coupling strengths, and rationalize the dispersion curves. The experimental results and the theoretical analysis presented here portray a way forward to the rational design of plexcitonic systems attaining the strong coupling limits.
Strong/weak coupling duality relations for non-supersymmetric string theories
International Nuclear Information System (INIS)
Blum, J.D.; Dienes, K.R.
1998-01-01
Both the supersymmetric SO(32) and E 8 x E 8 heterotic strings in ten dimensions have known strong-coupling duals. However, it has not been known whether there also exist strong-coupling duals for the non-supersymmetric heterotic strings in ten dimensions. In this paper, we construct explicit open-string duals for the circle compactifications of several of these non-supersymmetric theories, among them the tachyon-free SO(16) x SO(16) string. Our method involves the construction of heterotic and open-string interpolating models that continuously connect non-supersymmetric strings to supersymmetric strings. We find that our non-supersymmetric dual theories have exactly the same massless spectra as their heterotic counterparts within a certain range of our interpolations. We also develop a novel method for analyzing the solitons of non-supersymmetric open-string theories, and find that the solitons of our dual theories also agree with their heterotic counterparts. These are therefore the first known examples of strong/weak coupling duality relations between non-supersymmetric, tachyon-free string theories. Finally, the existence of these strong-coupling duals allows us to examine the non-perturbative stability of these strings, and we propose a phase diagram for the behavior of these strings as a function of coupling and radius. (orig.)
Cooling in the single-photon strong-coupling regime of cavity optomechanics
Nunnenkamp, A.; Børkje, K.; Girvin, S. M.
2012-05-01
In this Rapid Communication we discuss how red-sideband cooling is modified in the single-photon strong-coupling regime of cavity optomechanics where the radiation pressure of a single photon displaces the mechanical oscillator by more than its zero-point uncertainty. Using Fermi's golden rule we calculate the transition rates induced by the optical drive without linearizing the optomechanical interaction. In the resolved-sideband limit we find multiple-phonon cooling resonances for strong single-photon coupling that lead to nonthermal steady states including the possibility of phonon antibunching. Our study generalizes the standard linear cooling theory.
Angular Structure of Jet Quenching Within a Hybrid Strong/Weak Coupling Model
Casalderrey-Solana, Jorge; Milhano, Guilherme; Pablos, Daniel; Rajagopal, Krishna
2017-01-01
Within the context of a hybrid strong/weak coupling model of jet quenching, we study the modification of the angular distribution of the energy within jets in heavy ion collisions, as partons within jet showers lose energy and get kicked as they traverse the strongly coupled plasma produced in the collision. To describe the dynamics transverse to the jet axis, we add the effects of transverse momentum broadening into our hybrid construction, introducing a parameter $K\\equiv \\hat q/T^3$ that governs its magnitude. We show that, because of the quenching of the energy of partons within a jet, even when $K\
Three-loop Standard Model effective potential at leading order in strong and top Yukawa couplings
Energy Technology Data Exchange (ETDEWEB)
Martin, Stephen P. [Santa Barbara, KITP
2014-01-08
I find the three-loop contribution to the effective potential for the Standard Model Higgs field, in the approximation that the strong and top Yukawa couplings are large compared to all other couplings, using dimensional regularization with modified minimal subtraction. Checks follow from gauge invariance and renormalization group invariance. I also briefly comment on the special problems posed by Goldstone boson contributions to the effective potential, and on the numerical impact of the result on the relations between the Higgs vacuum expectation value, mass, and self-interaction coupling.
Strong enhancement of light-matter interaction in graphene coupled to a photonic crystal nanocavity.
Gan, Xuetao; Mak, Kin Fai; Gao, Yuanda; You, Yumeng; Hatami, Fariba; Hone, James; Heinz, Tony F; Englund, Dirk
2012-11-14
We demonstrate a large enhancement in the interaction of light with graphene through coupling with localized modes in a photonic crystal nanocavity. Spectroscopic studies show that a single atomic layer of graphene reduces the cavity reflection by more than a factor of one hundred, while also sharply reducing the cavity quality factor. The strong interaction allows for cavity-enhanced Raman spectroscopy on subwavelength regions of a graphene sample. A coupled-mode theory model matches experimental observations and indicates significantly increased light absorption in the graphene layer. The coupled graphene-cavity system also enables precise measurements of graphene's complex refractive index.
Thermal conductivity of magnetic insulators with strong spin-orbit coupling
Stamokostas, Georgios; Lapas, Panteleimon; Fiete, Gregory A.
We study the influence of spin-orbit coupling on the thermal conductivity of various types of magnetic insulators. In the absence of spin-orbit coupling and orbital-degeneracy, the strong-coupling limit of Hubbard interactions at half filling can often be adequately described in terms of a pure spin Hamiltonian of the Heisenberg form. However, in the presence of spin-orbit coupling the resulting exchange interaction can become highly anisotropic. The effect of the atomic spin-orbit coupling, taken into account through the effect of magnon-phonon interactions and the magnetic order and excitations, on the lattice thermal conductivity of various insulating magnetic systems is studied. We focus on the regime of low temperatures where the dominant source of scattering is two-magnon scattering to one-phonon processes. The thermal current is calculated within the Boltzmann transport theory. We are grateful for financial support from NSF Grant DMR-0955778.
Strong generalized synchronization with a particular relationship R between the coupled systems
Grácio, Clara; Fernandes, Sara; Mário Lopes, Luís
2018-03-01
The question of the chaotic synchronization of two coupled dynamical systems is an issue that interests researchers in many fields, from biology to psychology, through economics, chemistry, physics, and many others. The different forms of couplings and the different types of synchronization, give rise to many problems, most of them little studied. In this paper we deal with general couplings of two dynamical systems and we study strong generalized synchronization with a particular relationship R between them. Our results include the definition of a window in the domain of the coupling strength, where there is an exponentially stable solution, and the explicit determination of this window. In the case of unidirectional or symmetric couplings, this window is presented in terms of the maximum Lyapunov exponent of the systems. Examples of applications to chaotic systems of dimension one and two are presented.
Chen, Mo; Liu, Chao; Xian, Hao
2015-10-10
High-speed free-space optical communication systems using fiber-optic components can greatly improve the stability of the system and simplify the structure. However, propagation through atmospheric turbulence degrades the spatial coherence of the signal beam and limits the single-mode fiber (SMF) coupling efficiency. In this paper, we analyze the influence of the atmospheric turbulence on the SMF coupling efficiency over various turbulences. The results show that the SMF coupling efficiency drops from 81% without phase distortion to 10% when phase root mean square value equals 0.3λ. The simulations of SMF coupling with adaptive optics (AO) indicate that it is inevitable to compensate the high-order aberrations for SMF coupling over relatively strong turbulence. The SMF coupling efficiency experiments, using an AO system with a 137-element deformable mirror and a Hartmann-Shack wavefront sensor, obtain average coupling efficiency increasing from 1.3% in open loop to 46.1% in closed loop under a relatively strong turbulence, D/r0=15.1.
Sharma, Ramkishor; Jagannathan, Sandhya; Seshadri, T. R.; Subramanian, Kandaswamy
2017-10-01
Models of inflationary magnetogenesis with a coupling to the electromagnetic action of the form f2Fμ νFμ ν , are known to suffer from several problems. These include the strong coupling problem, the backreaction problem and also strong constraints due to the Schwinger effect. We propose a model which resolves all these issues. In our model, the coupling function, f , grows during inflation and transits to a decaying phase post-inflation. This evolutionary behavior is chosen so as to avoid the problem of strong coupling. By assuming a suitable power-law form of the coupling function, we can also neglect backreaction effects during inflation. To avoid backreaction post-inflation, we find that the reheating temperature is restricted to be below ≈1.7 ×104 GeV . The magnetic energy spectrum is predicted to be nonhelical and generically blue. The estimated present day magnetic field strength and the corresponding coherence length taking reheating at the QCD epoch (150 MeV) are 1.4 ×10-12 G and 6.1 ×10-4 Mpc , respectively. This is obtained after taking account of nonlinear processing over and above the flux-freezing evolution after reheating. If we consider also the possibility of a nonhelical inverse transfer, as indicated in direct numerical simulations, the coherence length and the magnetic field strength are even larger. In all cases mentioned above, the magnetic fields generated in our models satisfy the γ -ray bound below a certain reheating temperature.
Strong Coupling of a Quantum Oscillator to a Flux Qubit at Its Symmetry Point
Fedorov, A.; Feofanov, A.K.; Macha, P.; Forn-Díaz, P.; Harmans, C.J.P.M.; Mooij, J.E.
2010-01-01
A flux qubit biased at its symmetry point shows a minimum in the energy splitting (the gap), providing protection against flux noise. We have fabricated a qubit of which the gap can be tuned fast and have coupled this qubit strongly to an LC oscillator. We show full spectroscopy of the
Departures from predicted type II behavior in dirty strong-coupling superconductors
International Nuclear Information System (INIS)
Park, J.C.; Neighbor, J.E.; Shiffman, C.A.
1976-01-01
Calorimetric measurements of the Ginsburg-Landau parameters for Pb-Sn and Pb-Bi alloys show good agreement with the calculations of Rainer and Bergmann for kappa 1 (t)/kappa 1 (1). However, the calculations of Rainer and Usadel for kappa 2 (t)/kappa 2 (1) substantially underestimate the enhancements due to strong-coupling. (Auth.)
Fast-Projectile Stopping Power of Quantal Multicomponent Strongly Coupled Plasmas
International Nuclear Information System (INIS)
Ballester, D.; Tkachenko, I. M.
2008-01-01
The Bethe-Larkin formula for the fast-projectile stopping power is extended to multicomponent plasmas. The results are to contribute to the correct interpretation of the experimental data, which could permit us to test existing and future models of thermodynamic, static, and dynamic characteristics of strongly coupled Coulomb systems
Czech Academy of Sciences Publication Activity Database
Exner, Pavel; Pankrashkin, K.
2014-01-01
Roč. 39, č. 2 (2014), s. 193-212 ISSN 0360-5302 R&D Projects: GA ČR GAP203/11/0701 Institutional support: RVO:61389005 Keywords : Eigenvalue * Schrödinger operator * singular interaction * strong coupling * 35Q40 * 35P15 * 35J10 Subject RIV: BE - Theoretical Physics Impact factor: 1.013, year: 2014
Cusp anomalous dimension in maximally supersymmetric Yang-Mills theory at strong coupling.
Basso, B; Korchemsky, G P; Kotański, J
2008-03-07
We construct an analytical solution to the integral equation which is believed to describe logarithmic growth of the anomalous dimensions of high-spin operators in planar N=4 super Yang-Mills theory and use it to determine the strong coupling expansion of the cusp anomalous dimension.
Asymptotic dependence of Gross–Tulub polaron ground-state energy in the strong coupling region
Directory of Open Access Journals (Sweden)
N.I. Kashirina
2017-12-01
Full Text Available The properties of translationally invariant polaron functional have been investigated in the region of strong and extremely strong coupling. It has been shown that the Gross–Tulub polaron functional obtained earlier using the methods of field theory was derived only for the region , where is the Fröhlich constant of the electron-phonon coupling. Various representations of exact and approximate polaron functionals have been considered. Asymptotic dependences of the polaron energy have been obtained using a functional extending the Gross–Tulub functional to the region of extremely strong coupling. The asymptotic dependence of polaron energies for an extremely strong coupling are (for the one-parameter variational function fk, and (for a two-parameter function . It has been shown that the virial theorem 1:3:4 holds for the two-parameter function . Minimization of the approximate functional obtained by expanding the exact Gross–Tulub functional in a series on leads to a quadratic dependence of the polaron energy. This approximation is justified for . For a two-parameter function , the corresponding dependence has the form . However, the use of approximate functionals, in contrast to the strict variational procedure, when the exact polaron functional varies, does not guarantee obtaining the upper limit for the polaron energy.
Measurement of the Strong Coupling Constant from Inclusive Jet Production at the Tevatron Collider
Energy Technology Data Exchange (ETDEWEB)
Mesropian, Christina [Rockefeller Univ., New York, NY (United States)
2000-06-01
We present a measurement of the strong coupling constant from a single observable, the inclusive jet cross section. We use 86 pb^{-1} of data collected with the Collider Detector at Fermilab (CDF) from p$\\bar{p}$ collisions at √s = 1800 GeV. The data was analyzed and experimental systematic uncertainties estimated.
Multi-mode ultra-strong coupling in circuit quantum electrodynamics
Bosman, Sal J.; Gely, Mario F.; Singh, Vibhor; Bruno, Alessandro; Bothner, Daniel; Steele, Gary A.
2017-10-01
With the introduction of superconducting circuits into the field of quantum optics, many experimental demonstrations of the quantum physics of an artificial atom coupled to a single-mode light field have been realized. Engineering such quantum systems offers the opportunity to explore extreme regimes of light-matter interaction that are inaccessible with natural systems. For instance the coupling strength g can be increased until it is comparable with the atomic or mode frequency ωa,m and the atom can be coupled to multiple modes which has always challenged our understanding of light-matter interaction. Here, we experimentally realize a transmon qubit in the ultra-strong coupling regime, reaching coupling ratios of g/ωm = 0.19 and we measure multi-mode interactions through a hybridization of the qubit up to the fifth mode of the resonator. This is enabled by a qubit with 88% of its capacitance formed by a vacuum-gap capacitance with the center conductor of a coplanar waveguide resonator. In addition to potential applications in quantum information technologies due to its small size, this architecture offers the potential to further explore the regime of multi-mode ultra-strong coupling.
Towards corrections to the strong coupling limit of staggered lattice QCD
Fromm, Michael; Philipsen, Owe; de Forcrand, Philippe; Unger, Wolfgang; Miura, Kotaroh
2011-01-01
We report on the first steps of an ongoing project to add gauge observables and gauge corrections to the well-studied strong coupling limit of staggered lattice QCD, which has been shown earlier to be amenable to numerical simulations by the worm algorithm in the chiral limit and at finite density. Here we show how to evaluate the expectation value of the Polyakov loop in the framework of the strong coupling limit at finite temperature, allowing to study confinement properties along with those of chiral symmetry breaking. We find the Polyakov loop to rise smoothly, thus signalling deconfinement. The non-analytic nature of the chiral phase transition is reflected in the derivative of the Polyakov loop. We also discuss how to construct an effective theory for non-zero lattice coupling, which is valid to $O(\\beta)$.
Strong asymmetry for surface modes in nonlinear lattices with long-range coupling
International Nuclear Information System (INIS)
Martinez, Alejandro J.; Vicencio, Rodrigo A.; Molina, Mario I.
2010-01-01
We analyze the formation of localized surface modes on a nonlinear cubic waveguide array in the presence of exponentially decreasing long-range interactions. We find that the long-range coupling induces a strong asymmetry between the focusing and defocusing cases for the topology of the surface modes and also for the minimum power needed to generate them. In particular, for the defocusing case, there is an upper power threshold for exciting staggered modes, which depends strongly on the long-range coupling strength. The power threshold for dynamical excitation of surface modes increases (decreases) with the strength of long-range coupling for the focusing (defocusing) cases. These effects seem to be generic for discrete lattices with long-range interactions.
Strong light-matter coupling from atoms to solid-state systems
2014-01-01
The physics of strong light-matter coupling has been addressed in different scientific communities over the last three decades. Since the early eighties, atoms coupled to optical and microwave cavities have led to pioneering demonstrations of cavity quantum electrodynamics, Gedanken experiments, and building blocks for quantum information processing, for which the Nobel Prize in Physics was awarded in 2012. In the framework of semiconducting devices, strong coupling has allowed investigations into the physics of Bose gases in solid-state environments, and the latter holds promise for exploiting light-matter interaction at the single-photon level in scalable architectures. More recently, impressive developments in the so-called superconducting circuit QED have opened another fundamental playground to revisit cavity quantum electrodynamics for practical and fundamental purposes. This book aims at developing the necessary interface between these communities, by providing future researchers with a robust conceptu...
Energy Technology Data Exchange (ETDEWEB)
Angerer, Andreas, E-mail: andreas.angerer@tuwien.ac.at; Astner, Thomas; Wirtitsch, Daniel; Majer, Johannes, E-mail: johannes.majer@tuwien.ac.at [Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, Stadionallee 2, 1020 Vienna (Austria); Sumiya, Hitoshi [Sumitomo Electric Industries Ltd., Itami 664-001 (Japan); Onoda, Shinobu [Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Isoya, Junichi [Research Centre for Knowledge Communities, University of Tsukuba, 1-2 Kasuga, Tsukuba, Ibaraki 305-8550 (Japan); Putz, Stefan [Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, Stadionallee 2, 1020 Vienna (Austria); Department of Physics, Princeton University, Princeton, New Jersey 08544 (United States)
2016-07-18
We design and implement 3D-lumped element microwave cavities that spatially focus magnetic fields to a small mode volume. They allow coherent and uniform coupling to electron spins hosted by nitrogen vacancy centers in diamond. We achieve large homogeneous single spin coupling rates, with an enhancement of more than one order of magnitude compared to standard 3D cavities with a fundamental resonance at 3 GHz. Finite element simulations confirm that the magnetic field distribution is homogeneous throughout the entire sample volume, with a root mean square deviation of 1.54%. With a sample containing 10{sup 17} nitrogen vacancy electron spins, we achieve a collective coupling strength of Ω = 12 MHz, a cooperativity factor C = 27, and clearly enter the strong coupling regime. This allows to interface a macroscopic spin ensemble with microwave circuits, and the homogeneous Rabi frequency paves the way to manipulate the full ensemble population in a coherent way.
Self-induced steps in a small Josephson junction strongly coupled to a multimode resonator
DEFF Research Database (Denmark)
Larsen, A.; Jensen, H. Dalsgaard; Mygind, Jesper
1991-01-01
coupled systems. Based on a single-resonator model, we explain the exceptional size of the steps by the large content of higher harmonics of the Josephson oscillation sustained by the multiple modes of the resonator. The parameters of the junction and the loaded resonator—measured in situ by using......An equally spaced series of very large and nearly constant-voltage self-induced singularities has been observed in the dc I-V characteristics of a small Josephson tunnel junction strongly coupled to a resonant section of a superconducting transmission line. The system allows extremely high values...... of the coupling parameter. The current steps are due to subharmonic parametric excitation of the fundamental mode of the resonator loaded by the junction admittance. Using an applied magnetic field to vary the coupling parameter, we traced out half-integer steps as well as the mode steps known from more weakly...
Strong exciton-photon coupling in organic single crystal microcavity with high molecular orientation
Energy Technology Data Exchange (ETDEWEB)
Goto, Kaname [Department of Electronics, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Yamashita, Kenichi, E-mail: yamasita@kit.ac.jp [Faculty of Electrical Engineering and Electronics, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Yanagi, Hisao [Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan); Yamao, Takeshi; Hotta, Shu [Faculty of Materials Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan)
2016-08-08
Strong exciton-photon coupling has been observed in a highly oriented organic single crystal microcavity. This microcavity consists of a thiophene/phenylene co-oligomer (TPCO) single crystal laminated on a high-reflection distributed Bragg reflector. In the TPCO crystal, molecular transition dipole was strongly polarized along a certain horizontal directions with respect to the main crystal plane. This dipole polarization causes significantly large anisotropies in the exciton transition and optical constants. Especially the anisotropic exciton transition was found to provide the strong enhancement in the coupling with the cavity mode, which was demonstrated by a Rabi splitting energy as large as ∼100 meV even in the “half-vertical cavity surface emitting lasing” microcavity structure.
Simensen, Haakon T.; Linder, Jacob
2018-02-01
We present a theoretical description and numerical simulations of the superconducting transition in hybrid structures including strong spin-orbit interactions. The spin-orbit coupling is taken to be of Rashba type for concreteness, and we allow for an arbitrary magnitude of the spin-orbit strength as well as an arbitrary thickness of the spin-orbit coupled layer. This allows us to make contact with the experimentally relevant case of enhanced interfacial spin-orbit coupling via atomically thin heavy metal layers. We consider both interfacial spin-orbit coupling induced by inversion asymmetry in an S/F junction, as well as in-plane spin-orbit coupling in the ferromagnetic region of an S/F/S and an S/F structure. Both the pair amplitudes, local density of states, and critical temperature show dependency on the Rashba strength and, importantly, the orientation of the exchange field. In general, spin-orbit coupling increases the critical temperature of a proximity system where a magnetic field is present, and enhances the superconducting gap in the density of states. We perform a theoretical derivation which explains these results by the appearance of long-ranged singlet correlations. Our results suggest that Tc in ballistic spin-orbit coupled superconducting structures may be tuned by using only a single ferromagnetic layer.
Variational cluster approximation study of Mott transition with strong spin-orbit coupling
International Nuclear Information System (INIS)
Shirakawa, Tomonori; Watanabe, Hiroshi; Yunoki, Seiji
2011-01-01
Motivated by recent experiments on Sr 2 IrO 4 , the ground state magnetic and electronic structures are studied theoretically for a two-dimensional three-band Hubbard model with strong spin-orbit coupling. To treat spin-orbit coupling, local Coulomb interactions, and band structure effects on the same footing, the variational cluster approximation based on the self-energy functional theory is employed. It is found that for a relatively large coupling region, the ground state is an anisotropic antiferromagnetic Mott insulator of an effective local angular momentum J eff = 1/2 with xy plane as an easy plane. This anisotropy is caused by the strong spin-orbit coupling along with the inter-orbital Hund's coupling. The momentum resolved one-particle excitations are also studied for the Mott insulating phase. It is found that the low-energy one-particle excitations consist mostly of the J eff = 1/2 state, a direct evidence of a novel J eff = 1/2 Mott insulator.
Anisotropic shear viscosity of a strongly coupled non-Abelian plasma from magnetic branes
Critelli, R.; Finazzo, S. I.; Zaniboni, M.; Noronha, J.
2014-09-01
Recent estimates for the electromagnetic fields produced in the early stages of noncentral ultrarelativistic heavy ion collisions indicate the presence of magnetic fields B ˜O(0.1-15mπ2), where mπ is the pion mass. It is then of special interest to study the effects of strong (Abelian) magnetic fields on the transport coefficients of strongly coupled non-Abelian plasmas, such as the quark-gluon plasma formed in heavy ion collisions. In this paper we study the anisotropy in the shear viscosity induced by an external magnetic field in a strongly coupled N =4 super Yang-Mills (SYM) plasma. Due to the spatial anisotropy created by the magnetic field, the most general viscosity tensor of a magnetized plasma has five shear viscosity coefficients and two bulk viscosities. We use the holographic correspondence to evaluate two of the shear viscosities, η⊥≡ηxyxy (perpendicular to the magnetic field) and η∥≡ηxzxz=ηyzyz (parallel to the field). When B ≠0 the shear viscosity perpendicular to the field saturates the viscosity bound η⊥/s=1/(4π), while in the direction parallel to the field the bound is violated since η∥/s<1/(4π). However, the violation of the bound in the case of strongly coupled SYM is minimal even for the largest value of B that can be reached in heavy ion collisions.
Strong coupling in porphyrin J-aggregate excitons and plasmons in nano-void arrays
Ferdele, Stefano; Jose, Bincy; Foster, Robert; Keyes, Tia E.; Rice, James H.
2017-10-01
Active plasmonic nano-void arrays made through colloidal lithography (a cost effective and rapid process) potentially offers opportunities for scalable device design. In this work we demonstrate strong coupling between Bragg-like quadrupole surface plasmon modes in nano-void substrate designs with Frankel excitons in a molecular J-aggregate layer though angular tuning. The enhanced exciton-plasmon coupling creates a Fano like line shape in the differential reflection spectra associated with the formation of new hybrid states, leading to anti-crossing of the upper and lower polaritons with a Rabi frequency of 120 meV.
Study of the Higgs-Yukawa theory in the strong-Yukawa coupling regime
Bulava, John; Hou, George W.S.; Jansen, Karl; Knippschild, Bastian; Lin, C.J.David; Nagai, Kei-Ichi; Nagy, Attila; Ogawa, Kenji; Smigielski, Brian
2011-01-01
In this article, we present an ongoing lattice study of the Higgs-Yukawa model, in the regime of strong-Yukawa coupling, using overlap fermions. We investigated the phase structure in this regime by computing the Higgs vacuum expectation value, and by exploring the finite-size scaling behaviour of the susceptibility corresponding to the magnetisation. Our preliminary results indicate the existence of a second-order phase transition when the Yukawa coupling becomes large enough, at which the Higgs vacuum expectation value vanishes and the susceptibility diverges.
ac Stark shift and dephasing of a superconducting qubit strongly coupled to a cavity field.
Schuster, D I; Wallraff, A; Blais, A; Frunzio, L; Huang, R-S; Majer, J; Girvin, S M; Schoelkopf, R J
2005-04-01
We have performed spectroscopy of a superconducting charge qubit coupled nonresonantly to a single mode of an on-chip resonator. The strong coupling induces a large ac Stark shift in the energy levels of both the qubit and the resonator. The dispersive shift of the resonator frequency is used to nondestructively determine the qubit state. Photon shot noise in the measurement field induces qubit level fluctuations leading to dephasing which is characteristic for the measurement backaction. A crossover in line shape with measurement power is observed and theoretically explained. For weak measurement a long intrinsic dephasing time of T2>200 ns of the qubit is found.
Strong Coupling of Microwave Photons to Antiferromagnetic Fluctuations in an Organic Magnet
Mergenthaler, Matthias; Liu, Junjie; Le Roy, Jennifer J.; Ares, Natalia; Thompson, Amber L.; Bogani, Lapo; Luis, Fernando; Blundell, Stephen J.; Lancaster, Tom; Ardavan, Arzhang; Briggs, G. Andrew D.; Leek, Peter J.; Laird, Edward A.
2017-10-01
Coupling between a crystal of di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium radicals and a superconducting microwave resonator is investigated in a circuit quantum electrodynamics (circuit QED) architecture. The crystal exhibits paramagnetic behavior above 4 K, with antiferromagnetic correlations appearing below this temperature, and we demonstrate strong coupling at base temperature. The magnetic resonance acquires a field angle dependence as the crystal is cooled down, indicating anisotropy of the exchange interactions. These results show that multispin modes in organic crystals are suitable for circuit QED, offering a platform for their coherent manipulation. They also utilize the circuit QED architecture as a way to probe spin correlations at low temperature.
Simple model of a Feshbach resonance in the strong-coupling regime
Wasak, T.; Krych, M.; Idziaszek, Z.; Trippenbach, M.; Avishai, Y.; Band, Y. B.
2014-11-01
We use the dressed potentials obtained in the adiabatic representation of two coupled channels to calculate s -wave Feshbach resonances in a three-dimensional spherically symmetric potential with an open channel interacting with a closed channel. Analytic expressions for the s -wave scattering length a and number of resonances are obtained for a piecewise constant model with a piecewise constant interaction of the open and closed channels near the origin. We show analytically and numerically that, for strong enough coupling strength, Feshbach resonances can exist even when the closed channel does not have a bound state.
International Nuclear Information System (INIS)
Chaturvedi, D.K.; Senatore, G.; Tosi, M.P.
1980-10-01
An analytic theory is presented for the static structure factor of the one-component classical plasma at strong couplings. The theory combines the hard-core model of Gillan for short-range correlations in the Coulomb fluid with a semiempirical representation of intermediate-range correlations, through which the requirement of thermodynamic consistency on the ''compressibility'' and the known equation of state of the system are satisfied. Excellent agreement is found with the available computer simulation data on the structure of the fluid. The approach becomes inapplicable at intermediate and weak couplings where effects of penetration in the Coulomb hole of each particle become important. (author)
Achieving the classical Carnot efficiency in a strongly coupled quantum heat engine
Xu, Y. Y.; Chen, B.; Liu, J.
2018-02-01
Generally, the efficiency of a heat engine strongly coupled with a heat bath is less than the classical Carnot efficiency. Through a model-independent method, we show that the classical Carnot efficiency is achieved in a strongly coupled quantum heat engine. First, we present the first law of quantum thermodynamics in strong coupling. Then, we show how to achieve the Carnot cycle and the classical Carnot efficiency at strong coupling. We find that this classical Carnot efficiency stems from the fact that the heat released in a nonequilibrium process is balanced by the absorbed heat. We also analyze the restrictions in the achievement of the Carnot cycle. The first restriction is that there must be two corresponding intervals of the controllable parameter in which the corresponding entropies of the work substance at the hot and cold temperatures are equal, and the second is that the entropy of the initial and final states in a nonequilibrium process must be equal. Through these restrictions, we obtain the positive work conditions, including the usual one in which the hot temperature should be higher than the cold, and a new one in which there must be an entropy interval at the hot temperature overlapping that at the cold. We demonstrate our result through a paradigmatic model—a two-level system in which a work substance strongly interacts with a heat bath. In this model, we find that the efficiency may abruptly decrease to zero due to the first restriction, and that the second restriction results in the control scheme becoming complex.
Microscopic theory of photon-correlation spectroscopy in strong-coupling semiconductors
Energy Technology Data Exchange (ETDEWEB)
Schneebeli, Lukas
2009-11-27
While many quantum-optical phenomena are already well established in the atomic systems, like the photon antibunching, squeezing, Bose-Einstein condensation, teleportation, the quantum-optical investigations in semiconductors are still at their beginning. The fascinating results observed in the atomic systems inspire physicists to demonstrate similar quantum-optical effects also in the semiconductor systems. In contrast to quantum optics with dilute atomic gases, the semiconductors exhibit a complicated many-body problem which is dominated by the Coulomb interaction between the electrons and holes and by coupling with the semiconductor environment. This makes the experimental observation of similar quantum-optical effects in semiconductors demanding. However, there are already experiments which have verified nonclassical effects in semiconductors. In particular, experiments have demonstrated that semiconductor quantum dots (QDs) can exhibit the single-photon emission and generation of polarization-entangled photon pairs. In fact, both atom and QD systems, embedded within a microcavity, have become versatile platforms where one can perform systematic quantum-optics investigations as well as development work toward quantum-information applications. Another interesting field is the strong-coupling regime in which the light-matter coupling exceeds both the decoherence rate of the atom or QD and the cavity resulting in a reversible dynamics between light and matter excitations. In the strong-coupling regime, the Jaynes-Cummings ladder is predicted and shows a photon-number dependent splitting of the new dressed strong-coupling states which are the polariton states of the coupled light-matter system. Although the semiclassical effect of the vacuum Rabi splitting has already been observed in QDs, the verification of the quantum-mechanical Jaynes-Cummings splitting is still missing mainly due to the dephasing. Clearly, the observation of the Jaynes-Cummings ladder in QDs
Albarede, F.
2007-12-01
The canonical view of He isotope geochemistry holds that high 3He/4He ratios in basalts fingerprints undegassed mantle sources. Hawaiian basalts with unradiogenic He with 3He/4He up to 30 RA are therefore seen as originating from parts of the mantle that is still primordial, at least much more so than MORB mantle (3He/4He ~ 8 RA). This view was strongly reinforced by the discovery of solar and even planetary Ne components in oceanic basalts and gas wells. The canonical view, however, conflicts with multiple observations on ocean islands, notably Hawaiian basalts: the correlation of {187}Os/{186}Os with δ 18O combined with the presence of unusually radiogenic Hf isotope compositions for a given Nd isotope composition and the correlation between Hf and Pb isotopes are all features strongly reminiscent of ancient subducted oceanic crust and pelagic sediments in the source of the Hawaiian plume. These conflicting observations beg the question of how Hawaiian basalts, which carry the embodiment of a primordial gas signature, at the same time can provide such strong evidence of surface material recycling. I here suggest and alternative model that uses the marble cake paradigm and Shuster et al.'s data on olivine. A solution to this conundrum lies in an analogy with oil genesis: 3He and Ne do not reside in the low-melting point peridotites in which they were originally hosted but rather migrated since early in Earth history into refractory 'reservoir' rocks. Since there can be no free gas phase percolating at pressures in excess of olivine carbonation at ~3 GPa, He must be largely redistributed by diffusion. The time scale of diffusion is the defining parameter: although over billions of years 3He diffuses across large distances, melting events are too short to efficiently strip residual refractory rocks from their high-3He/4He component. Assuming that melts begin forming over the uppermost 100 km with an upwelling rate of 10 m y-1 in plume conduits and 10 cm y-1 under
Thermal Phase Transitions of Strongly Correlated Bosons with Spin-Orbit Coupling
Hickey, Ciarán; Paramekanti, Arun
2014-12-01
Experiments on ultracold atoms have started to explore lattice effects and thermal fluctuations for two-component bosons with spin-orbit coupling (SOC). Motivated by this, we derive and study a t J model for lattice bosons with equal Rashba-Dresselhaus SOC and strong Hubbard repulsion in a uniform Zeeman magnetic field. Using the Gutzwiller ansatz, we find strongly correlated ground states with stripe superfluid (SF) order. We formulate a finite temperature generalization of the Gutzwiller method, and show that thermal fluctuations in the doped Mott insulator drive a two-step melting of the stripe SF, revealing a wide regime of a stripe normal fluid.
Generic strong coupling behavior of Cooper pairs in the surface of superfluid nuclei
Energy Technology Data Exchange (ETDEWEB)
Pillet, N. [DPTA/Service de Physique nucleaire, CEA/DAM Ile de France, BP12, F-91680 Bruyeres-le-Chatel (France); Sandulescu, N. [DPTA/Service de Physique nucleaire, CEA/DAM Ile de France, BP12, F-91680 Bruyeres-le-Chatel (France)]|[Institute of Physics and Nuclear Engineering, 76900 Bucharest (Romania)]|[Institut de Physique Nucleaire, CNRS, UMR 8608, Orsay, F-91406 (France); Schuck, P. [Institut de Physique Nucleaire, CNRS, UMR 8608, Orsay, F-91406 (France)]|[Universite Paris-Sud, Orsay, F-91505 (France)
2007-01-15
With realistic HFB calculations, using the D1S Gogny force, we reveal a generic behavior of concentration of small sized Cooper pairs (2-3 fm) in the surface of superfluid nuclei. This study confirms and extends previous results given in the literature that use more schematic approaches. It is shown that the strong concentration of pair probability of small Cooper pairs in the nuclear surface is a quite general and generic feature and that nuclear pairing is much closer to the strong coupling regime than previously assumed.
Drag force in strongly coupled { N }=4 supersymmetric Yang–Mills plasma in a magnetic field
Zhang, Zi-qiang; Ma, Ke; Hou, De-fu
2018-02-01
Applying AdS/CFT correspondence, we study the effect of a constant magnetic field { B } on the drag force associated with a heavy quark moving through a strongly-coupled { N }=4 supersymmetric Yang–Mills plasma. The quark is considered moving transverse and parallel to { B }. It is shown that for transverse case, the drag force is linearly dependent on { B } in all regions, while for parallel case, the drag force increases monotonously with increasing { B } and also reveals a linear behavior in the regions of strong { B }. In addition, we find that { B } has a more important effect in the transverse case than for the parallel.
Strong coupling effects between a meta-atom and MIM nanocavity
Directory of Open Access Journals (Sweden)
San Chen
2012-09-01
Full Text Available In this paper, we investigate the strong coupling effects between a meta-atom and a metal-insulator-metal (MIM nanocavity. By changing the meta-atom sizes, we achieve the meta-atomic electric dipole, quadrupole or multipole interaction with the plasmonic nanocavity, in which characteristic anticrossing behaviors demonstrate the occurrence of the strong coupling. The various interactions present obviously different splitting values and behaviors of dependence on the meta-atomic position. The largest Rabi-type splittings, about 360.0 meV and 306.1 meV, have been obtained for electric dipole and quadrupole interaction, respectively. We attribute the large splitting to the highly-confined cavity mode and the large transition dipole of the meta-atom. Also the Rabi-type oscillation in time domain is given.
Review of strongly-coupled composite dark matter models and lattice simulations
Kribs, Graham D.; Neil, Ethan T.
2016-08-01
We review models of new physics in which dark matter arises as a composite bound state from a confining strongly-coupled non-Abelian gauge theory. We discuss several qualitatively distinct classes of composite candidates, including dark mesons, dark baryons, and dark glueballs. We highlight some of the promising strategies for direct detection, especially through dark moments, using the symmetries and properties of the composite description to identify the operators that dominate the interactions of dark matter with matter, as well as dark matter self-interactions. We briefly discuss the implications of these theories at colliders, especially the (potentially novel) phenomenology of dark mesons in various regimes of the models. Throughout the review, we highlight the use of lattice calculations in the study of these strongly-coupled theories, to obtain precise quantitative predictions and new insights into the dynamics.
Equivalence of meson scattering amplitudes in strong coupling lattice and flat space string theory
Armoni, Adi; Ireson, Edwin; Vadacchino, Davide
2018-03-01
We consider meson scattering in the framework of the lattice strong coupling expansion. In particular we derive an expression for the 4-point function of meson operators in the planar limit of scalar Chromodynamics. Interestingly, in the naive continuum limit the expression coincides with an independently known result, that of the worldline formalism. Moreover, it was argued by Makeenko and Olesen that (assuming confinement) the resulting scattering amplitude in momentum space is the celebrated expression proposed by Veneziano several decades ago. This motivates us to also use holography in order to argue that the continuum expression for the scattering amplitude is related to the result obtained from flat space string theory. Our results hint that at strong coupling and large-Nc the naive continuum limit of the lattice formalism can be related to a flat space string theory.
Wilson loop correlators at strong coupling: from matrices to bubbling geometries
Gomis, Jaume; Matsuura, Shunji; Okuda, Takuya; Trancanelli, Diego
2008-08-01
We compute at strong coupling the large N correlation functions of supersymmetric Wilson loops in large representations of the gauge group with local operators of Script N = 4 super Yang-Mills. The gauge theory computation of these correlators is performed using matrix model techniques. We show that the strong coupling correlator of the Wilson loop with the stress tensor computed using the matrix model exactly matches the semiclassical computation of the correlator of the 't Hooft loop with the stress tensor, providing a non-trivial quantitative test of electric-magnetic duality of Script N = 4 super Yang-Mills. We then perform these calculations using the dual bulk gravitational picture, where the Wilson loop is described by a ``bubbling'' geometry. By applying holographic methods to these backgrounds we calculate the Wilson loop correlation functions, finding perfect agreement with our gauge theory results.
Sensitive Detection of Individual Neutral Atoms in a Strong Coupling Cavity QED System
International Nuclear Information System (INIS)
Zhang Peng-Fei; Zhang Yu-Chi; Li Gang; Du Jin-Jin; Zhang Yan-Feng; Guo Yan-Qiang; Wang Jun-Min; Zhang Tian-Cai; Li Wei-Dong
2011-01-01
We experimentally demonstrate real-time detection of individual cesium atoms by using a high-finesse optical micro-cavity in a strong coupling regime. A cloud of cesium atoms is trapped in a magneto-optical trap positioned at 5 mm above the micro-cavity center. The atoms fall down freely in gravitation after shutting off the magneto-optical trap and pass through the cavity. The cavity transmission is strongly affected by the atoms in the cavity, which enables the micro-cavity to sense the atoms individually. We detect the single atom transits either in the resonance or various detunings. The single atom vacuum-Rabi splitting is directly measured to be Ω = 2π × 23.9 MHz. The average duration of atom-cavity coupling of about 110 μs is obtained according to the probability distribution of the atom transits. (fundamental areas of phenomenology(including applications))
Particularities of surface plasmon-exciton strong coupling with large Rabi splitting
International Nuclear Information System (INIS)
Symonds, C; Bonnand, C; Plenet, J C; Brehier, A; Parashkov, R; Lauret, J S; Deleporte, E; Bellessa, J
2008-01-01
This paper presents some of the particularities of the strong coupling regime occurring between surface plasmon (SP) modes and excitons. Two different active materials were deposited on a silver film: a cyanine dye J-aggregate, and a two-dimensional layered perovskite-type semiconductor. The dispersion relations, which are deduced from angular resolved reflectometry spectra, present an anticrossing characteristic of the strong coupling regime. The wavevector is a good parameter to determine the Rabi splitting. Due to the large interaction energies (several hundreds of milli-electron-volts), the calculations at constant angle can induce an overestimation of the Rabi splitting of more than a factor of two. Another property of polaritons based on SP is their nonradiative character. In order to observe the polaritonic emission, it is thus necessary to use particular extraction setups, such as gratings or prisms. Otherwise only the incoherent emission can be detected, very similar to the bare exciton emission
Sakata Memorial KMI Workshop on Origin of Mass and Strong Coupling Gauge Theories
Maskawa, Toshihide; Nojiri, Shin'ichi; Tanabashi, Masaharu; Yamawaki, Koichi
2018-01-01
This volume contains contributions to the workshop, which was largely focused on the strong coupling gauge theories in search for theories beyond the standard model, particularly, the LHC experiments and lattice studies of conformal fixed point. The main topics include walking technicolor and the role of conformality in view of the 125 GeV Higgs as a light composite Higgs (technidilaton, and other composite Higgs, etc.). Nonperturbative studies like lattice simulations and stringy/holographic approaches are extensively discussed in close relation to the phenomenological studies. After the discovery of 125 GeV Higgs at LHC, the central issue of particle physics is now to reveal the dynamical origin of the Higgs itself. One of the possibilities would be the composite Higgs based on the strong coupling gauge theory in the TeV region, such as the technidilaton predicted in walking technicolor with infrared conformality. The volume contains, among others, many of the latest important reports on walking technicolo...
International Nuclear Information System (INIS)
Tzimis, A.; Savvidis, P. G.; Trifonov, A. V.; Ignatiev, I. V.; Christmann, G.; Tsintzos, S. I.; Hatzopoulos, Z.; Kavokin, A. V.
2015-01-01
We report observation of strong light-matter coupling in an AlGaAs microcavity (MC) with an embedded single parabolic quantum well. The parabolic potential is achieved by varying aluminum concentration along the growth direction providing equally spaced energy levels, as confirmed by Brewster angle reflectivity from a reference sample without MC. It acts as an active region of the structure which potentially allows cascaded emission of terahertz (THz) light. Spectrally and time resolved pump-probe spectroscopy reveals characteristic quantum beats whose frequencies range from 0.9 to 4.5 THz, corresponding to energy separation between relevant excitonic levels. The structure exhibits strong stimulated nonlinear emission with simultaneous transition to weak coupling regime. The present study highlights the potential of such devices for creating cascaded relaxation of bosons, which could be utilized for THz emission
Equivalence of meson scattering amplitudes in strong coupling lattice and flat space string theory
Directory of Open Access Journals (Sweden)
Adi Armoni
2018-03-01
Full Text Available We consider meson scattering in the framework of the lattice strong coupling expansion. In particular we derive an expression for the 4-point function of meson operators in the planar limit of scalar Chromodynamics. Interestingly, in the naive continuum limit the expression coincides with an independently known result, that of the worldline formalism. Moreover, it was argued by Makeenko and Olesen that (assuming confinement the resulting scattering amplitude in momentum space is the celebrated expression proposed by Veneziano several decades ago. This motivates us to also use holography in order to argue that the continuum expression for the scattering amplitude is related to the result obtained from flat space string theory. Our results hint that at strong coupling and large-Nc the naive continuum limit of the lattice formalism can be related to a flat space string theory.
Strong-coupling behaviour of two t - J chains with interchain single-electron hopping
International Nuclear Information System (INIS)
Zhang Guangming; Feng Shiping; Yu Lu.
1994-01-01
Using the fermion-spin transformation to implement spin-charge separation of constrained electrons, a model of two t - J chains with interchain single-electron hopping is studied by abelian bosonization. After spin-charge decoupling the charge dynamics can be trivially solved, while the spin dynamics is determined by a strong-coupling fixed point where the correlation functions can be calculated explicitly. This is a generalization of the Luther-Emery line for two-coupled t - J chains. The interchain single-electron hopping changes the asymptotic behaviour of the interchain spin-spin correlation functions and the electron Green function, but their exponents are independent of the coupling strength. (author). 25 refs
Effective hadronic lagrangian in the strong coupling expansion of lattice QCD with Susskind fermions
International Nuclear Information System (INIS)
Azakov, S.I.; Aliev, E.S.
1987-12-01
The effective hadronic action in lattice QCD with U(N) and SU(N) gauge groups and with Susskind fermions is constructed in the framework of the strong coupling approximation. For arbitrary finite (odd) N (in particular N=3) we find an effective potential, vacuum expectation value of the (χ-barχ) and an effective action for the physical meson field π(x). (author). 19 refs
Dynamic properties of one-component strongly coupled plasmas: The sum-rule approach
International Nuclear Information System (INIS)
Arkhipov, Yu. V.; Askaruly, A.; Davletov, A. E.; Ballester, D.; Tkachenko, I. M.; Zwicknagel, G.
2010-01-01
The dynamic characteristics of strongly coupled one-component plasmas are studied within the moment approach. Our results on the dynamic structure factor and the dynamic local-field correction satisfy the sum rules and other exact relations automatically. A quantitative agreement is obtained with numerous simulation data on the plasma dynamic properties, including the dispersion and decay of collective modes. Our approach allows us to correct and complement the results previously found with other treatments.
Strongly coupled chameleon fields: Possible test with a neutron Lloyd's mirror interferometer
Energy Technology Data Exchange (ETDEWEB)
Pokotilovski, Yu.N., E-mail: pokot@nf.jinr.ru [Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region (Russian Federation)
2013-02-26
The consideration of possible neutron Lloyd's mirror interferometer experiment to search for strongly coupled chameleon fields is presented. The chameleon scalar fields were proposed to explain the acceleration of expansion of the Universe. The presence of a chameleon field results in a change of a particle's potential energy in vicinity of a massive body. This interaction causes a phase shift of neutron waves in the interferometer. The sensitivity of the method is estimated.
Breakdown of the 1/N expansion in the continuum limit of strong coupling lattice QCD
International Nuclear Information System (INIS)
Bralic, N.; Pontificia Universidade Catolica de Chile, Santiago. Facultad de Fisica); Loewe, M.
1983-08-01
The restoration of lorentz covariance in the continuum limit of strong coupling lattice QCD is shown to require the breakdown of the 1/N expansion. With the leading 1/N appoximation becoming irrelevant in that limit. To leading order in 1/N lorentz convariance can be restored only as an approximate long distance symmetry a non conventional continuum limit with a non hermitian hamiltonian. (Author) [pt
Fermion bag approach to the sign problem in strongly coupled lattice QED with Wilson fermions
Chandrasekharan, Shailesh; Li, Anyi
2010-01-01
We explore the sign problem in strongly coupled lattice QED with one flavor of Wilson fermions in four dimensions using the fermion bag formulation. We construct rules to compute the weight of a fermion bag and show that even though the fermions are confined into bosons, fermion bags with negative weights do exist. By classifying fermion bags as either simple or complex, we find numerical evidence that complex bags with positive and negative weights come with almost equal probabilities and th...
Room temperature strong light-matter coupling in 3D THz meta-atoms (Conference Presentation)
Paulillo, Bruno; Manceau, Jean-Michel; Li, Lianhe; Linfield, Edmund; Colombelli, Raffaele
2016-04-01
We demonstrate strong light-matter coupling at room temperature in the terahertz (THz) spectral region using 3D meta-atoms with extremely sub-wavelength volumes. Using an air-bridge fabrication scheme, we have implemented sub-wavelength 3D THz micro-resonators that rely on suspended loop antennas connected to semiconductor-filled patch cavities. We have experimentally shown that they possess the functionalities of lumped LC resonators: their frequency response can be adjusted by independently tuning the inductance associated the antenna element or the capacitance provided by the metal-semiconductor-metal cavity. Moreover, the radiation coupling and efficiency can be engineered acting on the design of the loop antenna, similarly to conventional RF antennas. Here we take advantage of this rich playground in the context of cavity electrodynamics/intersubband polaritonics. In the strong light-matter coupling regime, a cavity and a two-level system exchange energy coherently at a characteristic rate called the vacuum Rabi frequency ΩR which is dominant with respect to all other loss mechanisms involved. The signature, in the frequency domain, is the appearance of a splitting between the bare cavity and material system resonances: the new states are called upper and a lower polariton branches. So far, most experimental demonstrations of strong light-matter interaction between an intersubband transition and a deeply sub-wavelength mode in the THz or mid-infrared ranges rely on wavelength-scale or larger resonators such as photonic crystals, diffractive gratings, dielectric micro-cavities or patch cavities. Lately, planar metamaterials have been used to enhance the light-matter interaction and strongly reduce the interaction volume by engineering the electric and magnetic resonances of the individual subwavelength constituents. In this contribution we provide evidence of strong coupling between a THz intersubband transition and an extremely sub-wavelength mode (≈λ/10
Energy Technology Data Exchange (ETDEWEB)
Prajapati, R. P., E-mail: prajapati-iter@yahoo.co.in; Bhakta, S. [Department of Pure and Applied Physics, Guru Ghasidas Central University, Bilaspur-495009 (C.G.) (India); Chhajlani, R. K. [Retired from School of Studies in Physics, Vikram University, Ujjain-456010 (M.P.) (India)
2016-05-15
The influence of dust-neutral collisions, polarization force, and electron radiative condensation is analysed on the Jeans (gravitational) instability of partially ionized strongly coupled dusty plasma (SCDP) using linear perturbation (normal mode) analysis. The Boltzmann distributed ions, dynamics of inertialess electrons, charged dust and neutral particles are considered. Using the plane wave solutions, a general dispersion relation is derived which is modified due to the presence of dust-neutral collisions, strong coupling effect, polarization force, electron radiative condensation, and Jeans dust/neutral frequencies. In the long wavelength perturbations, the Jeans instability criterion depends upon strong coupling effect, polarization interaction parameter, and thermal loss, but it is independent of dust-neutral collision frequency. The stability of the considered configuration is analysed using the Routh–Hurwitz criterion. The growth rates of Jeans instability are illustrated, and stabilizing influence of viscoelasticity and dust-neutral collision frequency while destabilizing effect of electron radiative condensation, polarization force, and Jeans dust-neutral frequency ratio is observed. This work is applied to understand the gravitational collapse of SCDP with dust-neutral collisions.
The NEON Aquatic Network: Expanding the Availability of Biogeochemical Data
Vance, J. M.; Bohall, C.; Fitzgerald, M.; Utz, R.; Parker, S. M.; Roehm, C. L.; Goodman, K. J.; McLaughlin, B.
2013-12-01
Aquatic ecosystems are facing unprecedented pressure from climate change and land-use practices. Invasive species, whether plant, animal, insect or microbe present additional threat to aquatic ecosystem services. There are significant scientific challenges to understanding how these forces will interact to affect aquatic ecosystems, as the flow of energy and materials in the environment is driven by multivariate and non-linear biogeochemical cycles. The National Ecological Observatory Network (NEON) will collect and provide observational data across multiple scales. Sites were selected to maximize representation of major North American ecosystems using a multivariate geographic clustering method that partitioned the continental US, AK, HI, and Puerto Rico into 20 eco-climatic domains. The NEON data collection systems and methods are designed to yield standardized, near real-time data subjected to rigorous quality controls prior to public dissemination through an online data portal. NEON will collect data for 30 years to facilitate spatial-temporal analysis of environmental responses and drivers of ecosystem change, ranging from local through continental scales. Here we present the NEON Aquatic Network, a multi-parameter network consisting of a combination of in situ sensor and observational data. This network will provide data to examine biogeochemical, biological, hydrologic and geomorphic metrics at 36 sites, which are a combination of small 1st/2nd order wadeable streams, large rivers and lakes. A typical NEON Aquatic site will host up to two in-stream sensor sets designed to collect near-continuous water quality data (e.g. pH/ORP, temperature, conductivity, dissolved oxygen, CDOM) along with up to 8 shallow groundwater monitoring wells (level, temp., cond.), and a local meteorological station (e.g. 2D wind speed, PAR, barometric pressure, temperature, net radiation). These coupled sensor suites will be complemented by observational data (e.g. water
Demonstrating Fluorescence with Neon Paper and Plastic
Birriel, Jennifer J.; Roe, Clarissa
2015-01-01
Several papers in this journal have dealt with the fluorescence in orange neon plastic, olive oil, and soda. In each case, the fluorescent emission was excited by either green or violet-blue laser light. In this paper, we examine the fluorescent emission spectra of so-called neon colored papers and plastic clipboards available in department and…
Constraints on parton distributions and the strong coupling from LHC jet data
Rojo, Juan
2015-11-01
Jet production at hadron colliders provides powerful constraints on the parton distribution functions (PDFs) of the proton, in particular on the gluon PDF. Jet production can also be used to extract the QCD coupling αs(Q) and to test its running with the momentum transfer up to the TeV region. In this review, I summarize the information on PDFs and the strong coupling that has been provided by Run I LHC jet data. First of all, I discuss why jet production is directly sensitive to the gluon and quark PDFs at large-x, and then review the state-of-the-art perturbative calculations for jet production at hadron colliders and the corresponding fast calculations required for PDF fitting. Then I present the results of various recent studies on the impact on PDFs, in particular the gluon, that have been performed using as input jet measurements from ATLAS and CMS. I also review the available determinations of the strong coupling constant based on ATLAS and CMS jet data, with emphasis on the fact that LHC jet data provides, for the first time, a direct test of the αs(Q) running at the TeV scale. I conclude with a brief outlook on possible future developments.
Oblique S and T constraints on electroweak strongly-coupled models with a light Higgs
Energy Technology Data Exchange (ETDEWEB)
Pich, A. [Departament de Física Teòrica, IFIC, Universitat de València - CSIC,Apt. Correus 22085, E-46071 València (Spain); Rosell, I. [Departament de Física Teòrica, IFIC, Universitat de València - CSIC,Apt. Correus 22085, E-46071 València (Spain); Departamento de Ciencias Físicas, Matemáticas y de la Computación,Universidad CEU Cardenal Herrera,c/ Sant Bartomeu 55, E-46115 Alfara del Patriarca, València (Spain); Sanz-Ciller, J.J. [Departamento de Física Teórica, Instituto de Física Teórica,Universidad Autónoma de Madrid - CSIC,c/ Nicolás Cabrera 13-15, E-28049 Cantoblanco, Madrid (Spain)
2014-01-28
Using a general effective Lagrangian implementing the chiral symmetry breaking SU(2){sub L}⊗SU(2){sub R}→SU(2){sub L+R}, we present a one-loop calculation of the oblique S and T parameters within electroweak strongly-coupled models with a light scalar. Imposing a proper ultraviolet behaviour, we determine S and T at next-to-leading order in terms of a few resonance parameters. The constraints from the global fit to electroweak precision data force the massive vector and axial-vector states to be heavy, with masses above the TeV scale, and suggest that the W{sup +}W{sup −} and ZZ couplings of the Higgs-like scalar should be close to the Standard Model value. Our findings are generic, since they only rely on soft requirements on the short-distance properties of the underlying strongly-coupled theory, which are widely satisfied in more specific scenarios.
Ghodrat, Malihe; Naji, Ali; Komaie-Moghaddam, Haniyeh; Podgornik, Rudolf
2015-05-07
We study the effective interaction mediated by strongly coupled Coulomb fluids between dielectric surfaces carrying quenched, random monopolar charges with equal mean and variance, both when the Coulomb fluid consists only of mobile multivalent counterions and when it consists of an asymmetric ionic mixture containing multivalent and monovalent (salt) ions in equilibrium with an aqueous bulk reservoir. We analyze the consequences that follow from the interplay between surface charge disorder, dielectric and salt image effects, and the strong electrostatic coupling that results from multivalent counterions on the distribution of these ions and the effective interaction pressure they mediate between the surfaces. In a dielectrically homogeneous system, we show that the multivalent counterions are attracted towards the surfaces with a singular, disorder-induced potential that diverges logarithmically on approach to the surfaces, creating a singular but integrable counterion density profile that exhibits an algebraic divergence at the surfaces with an exponent that depends on the surface charge (disorder) variance. This effect drives the system towards a state of lower thermal 'disorder', one that can be described by a renormalized temperature, exhibiting thus a remarkable antifragility. In the presence of an interfacial dielectric discontinuity, the singular behavior of counterion density at the surfaces is removed but multivalent counterions are still accumulated much more strongly close to randomly charged surfaces as compared with uniformly charged ones. The interaction pressure acting on the surfaces displays in general a highly non-monotonic behavior as a function of the inter-surface separation with a prominent regime of attraction at small to intermediate separations. This attraction is caused directly by the combined effects from charge disorder and strong coupling electrostatics of multivalent counterions, which dominate the surface-surface repulsion due to
Strong coupling in F-theory and geometrically non-Higgsable seven-branes
Directory of Open Access Journals (Sweden)
James Halverson
2017-06-01
Full Text Available Geometrically non-Higgsable seven-branes carry gauge sectors that cannot be broken by complex structure deformation, and there is growing evidence that such configurations are typical in F-theory. We study strongly coupled physics associated with these branes. Axiodilaton profiles are computed using Ramanujan's theories of elliptic functions to alternative bases, showing explicitly that the string coupling is O(1 in the vicinity of the brane; that it sources nilpotent SL(2,Z monodromy and therefore the associated brane charges are modular; and that essentially all F-theory compactifications have regions with order one string coupling. It is shown that non-perturbative SU(3 and SU(2 seven-branes are related to weakly coupled counterparts with D7-branes via deformation-induced Hanany–Witten moves on (p,q string junctions that turn them into fundamental open strings; only the former may exist for generic complex structure. D3-brane near these and the Kodaira type II seven-branes probe Argyres–Douglas theories. The BPS states of slightly deformed theories are shown to be dyonic string junctions.
Liang, Yongye; Wang, Hailiang; Diao, Peng; Chang, Wesley; Hong, Guosong; Li, Yanguang; Gong, Ming; Xie, Liming; Zhou, Jigang; Wang, Jian; Regier, Tom Z; Wei, Fei; Dai, Hongjie
2012-09-26
Electrocatalyst for oxygen reduction reaction (ORR) is crucial for a variety of renewable energy applications and energy-intensive industries. The design and synthesis of highly active ORR catalysts with strong durability at low cost is extremely desirable but remains challenging. Here, we used a simple two-step method to synthesize cobalt oxide/carbon nanotube (CNT) strongly coupled hybrid as efficient ORR catalyst by directly growing nanocrystals on oxidized multiwalled CNTs. The mildly oxidized CNTs provided functional groups on the outer walls to nucleate and anchor nanocrystals, while retaining intact inner walls for highly conducting network. Cobalt oxide was in the form of CoO due to a gas-phase annealing step in NH(3). The resulting CoO/nitrogen-doped CNT (NCNT) hybrid showed high ORR current density that outperformed Co(3)O(4)/graphene hybrid and commercial Pt/C catalyst at medium overpotential, mainly through a 4e reduction pathway. The metal oxide/carbon nanotube hybrid was found to be advantageous over the graphene counterpart in terms of active sites and charge transport. Last, the CoO/NCNT hybrid showed high ORR activity and stability under a highly corrosive condition of 10 M NaOH at 80 °C, demonstrating the potential of strongly coupled inorganic/nanocarbon hybrid as a novel catalyst system in oxygen depolarized cathode for chlor-alkali electrolysis.
Charging-delay effect on longitudinal dust acoustic shock wave in strongly coupled dusty plasma
International Nuclear Information System (INIS)
Ghosh, Samiran; Gupta, M.R.
2005-01-01
Taking into account the charging-delay effect, the nonlinear propagation characteristics of longitudinal dust acoustic wave in strongly coupled collisional dusty plasma described by generalized hydrodynamic model have been investigated. In the 'hydrodynamic limit', a Korteweg-de Vries Burger (KdVB) equation with a damping term arising due to dust-neutral collision is derived in which the Burger term is proportional to the dissipation due to dust viscosity through dust-dust correlation and charging-delay-induced anomalous dissipation. On the other hand, in the 'kinetic limit', a KdVB equation with a damping term and a nonlocal nonlinear forcing term arising due to memory-dependent strong correlation effect of dust fluid is derived in which the Burger term depends only on the charging-delay-induced dissipation. Numerical solution of integrodifferential equations reveals that (i) dissipation due to dust viscosity and principally due to charging delay causes excitation of the longitudinal dust acoustic shock wave in strongly coupled dusty plasma and (ii) dust-neutral collision does not appear to play any direct role in shock formation. The condition for the generation of shock is also discussed briefly
Treating Sample Covariances for Use in Strongly Coupled Atmosphere-Ocean Data Assimilation
Smith, Polly J.; Lawless, Amos S.; Nichols, Nancy K.
2018-01-01
Strongly coupled data assimilation requires cross-domain forecast error covariances; information from ensembles can be used, but limited sampling means that ensemble derived error covariances are routinely rank deficient and/or ill-conditioned and marred by noise. Thus, they require modification before they can be incorporated into a standard assimilation framework. Here we compare methods for improving the rank and conditioning of multivariate sample error covariance matrices for coupled atmosphere-ocean data assimilation. The first method, reconditioning, alters the matrix eigenvalues directly; this preserves the correlation structures but does not remove sampling noise. We show that it is better to recondition the correlation matrix rather than the covariance matrix as this prevents small but dynamically important modes from being lost. The second method, model state-space localization via the Schur product, effectively removes sample noise but can dampen small cross-correlation signals. A combination that exploits the merits of each is found to offer an effective alternative.
Shear viscosity of strongly coupled N = 4 supersymmetric Yang-Mills plasma.
Policastro, G; Son, D T; Starinets, A O
2001-08-20
Using the anti-de Sitter/conformal field theory correspondence, we relate the shear viscosity eta of the finite-temperature N = 4 supersymmetric Yang-Mills theory in the large N, strong-coupling regime with the absorption cross section of low-energy gravitons by a near-extremal black three-brane. We show that in the limit of zero frequency this cross section coincides with the area of the horizon. From this result we find eta = pi / 8N(2)T3. We conjecture that for finite 't Hooft coupling g(2)(YM)N the shear viscosity is eta = f(g(2)(YM)N)N2T3, where f(x) is a monotonic function that decreases from O(x(-2)ln(-1)(1/x)) at small x to pi/8 when x-->infinity.
Gnoffo, Peter A.; Johnston, Christopher O.
2011-01-01
Implementations of a model for equilibrium, steady-state ablation boundary conditions are tested for the purpose of providing strong coupling with a hypersonic flow solver. The objective is to remove correction factors or film cooling approximations that are usually applied in coupled implementations of the flow solver and the ablation response. Three test cases are considered - the IRV-2, the Galileo probe, and a notional slender, blunted cone launched at 10 km/s from the Earth's surface. A successive substitution is employed and the order of succession is varied as a function of surface temperature to obtain converged solutions. The implementation is tested on a specified trajectory for the IRV-2 to compute shape change under the approximation of steady-state ablation. Issues associated with stability of the shape change algorithm caused by explicit time step limits are also discussed.
Hanle Magnetoresistance in Thin Metal Films with Strong Spin-Orbit Coupling.
Vélez, Saül; Golovach, Vitaly N; Bedoya-Pinto, Amilcar; Isasa, Miren; Sagasta, Edurne; Abadia, Mikel; Rogero, Celia; Hueso, Luis E; Bergeret, F Sebastian; Casanova, Fèlix
2016-01-08
We report measurements of a new type of magnetoresistance in Pt and Ta thin films. The spin accumulation created at the surfaces of the film by the spin Hall effect decreases in a magnetic field because of the Hanle effect, resulting in an increase of the electrical resistance as predicted by Dyakonov [Phys. Rev. Lett. 99, 126601 (2007)]. The angular dependence of this magnetoresistance resembles the recently discovered spin Hall magnetoresistance in Pt/Y(3)Fe(5)O(12) bilayers, although the presence of a ferromagnetic insulator is not required. We show that this Hanle magnetoresistance is an alternative simple way to quantitatively study the coupling between charge and spin currents in metals with strong spin-orbit coupling.
Strong-coupling Bose polarons out of equilibrium: Dynamical renormalization-group approach
Grusdt, Fabian; Seetharam, Kushal; Shchadilova, Yulia; Demler, Eugene
2018-03-01
When a mobile impurity interacts with a surrounding bath of bosons, it forms a polaron. Numerous methods have been developed to calculate how the energy and the effective mass of the polaron are renormalized by the medium for equilibrium situations. Here, we address the much less studied nonequilibrium regime and investigate how polarons form dynamically in time. To this end, we develop a time-dependent renormalization-group approach which allows calculations of all dynamical properties of the system and takes into account the effects of quantum fluctuations in the polaron cloud. We apply this method to calculate trajectories of polarons following a sudden quench of the impurity-boson interaction strength, revealing how the polaronic cloud around the impurity forms in time. Such trajectories provide additional information about the polaron's properties which are challenging to extract directly from the spectral function measured experimentally using ultracold atoms. At strong couplings, our calculations predict the appearance of trajectories where the impurity wavers back at intermediate times as a result of quantum fluctuations. Our method is applicable to a broader class of nonequilibrium problems. As a check, we also apply it to calculate the spectral function and find good agreement with experimental results. At very strong couplings, we predict that quantum fluctuations lead to the appearance of a dark continuum with strongly suppressed spectral weight at low energies. While our calculations start from an effective Fröhlich Hamiltonian describing impurities in a three-dimensional Bose-Einstein condensate, we also calculate the effects of additional terms in the Hamiltonian beyond the Fröhlich paradigm. We demonstrate that the main effect of these additional terms on the attractive side of a Feshbach resonance is to renormalize the coupling strength of the effective Fröhlich model.
Strong coupling on a forbidden transition in strontium and nondestructive atom counting
Norcia, Matthew A.; Thompson, James K.
2016-02-01
We observe strong collective coupling between an optical cavity and the forbidden spin singlet to triplet optical transition S10 to P31 in an ensemble of 88Sr. Despite the transition being 1000 times weaker than a typical dipole transition, we observe a well-resolved vacuum Rabi splitting. We use the observed vacuum Rabi splitting to make nondestructive measurements of atomic population with the equivalent of projection-noise limited sensitivity between subsequent measurements and with minimal heating [lattice clocks by generating entangled states and reducing dead time.
A strongly conservative finite element method for the coupling of Stokes and Darcy flow
Kanschat, G.
2010-08-01
We consider a model of coupled free and porous media flow governed by Stokes and Darcy equations with the Beavers-Joseph-Saffman interface condition. This model is discretized using divergence-conforming finite elements for the velocities in the whole domain. Discontinuous Galerkin techniques and mixed methods are used in the Stokes and Darcy subdomains, respectively. This discretization is strongly conservative in Hdiv(Ω) and we show convergence. Numerical results validate our findings and indicate optimal convergence orders. © 2010 Elsevier Inc.
Radiation of a circulating quark in strongly coupled N = 4 super Yang-Mills theory
Athanasiou, Christiana; Chesler, Paul M.; Liu, Hong; Nickel, Dominik; Rajagopal, Krishna
2010-12-01
The energy density and angular distribution of power radiated by a quark undergoing circular motion in strongly coupled N = 4 supersymmetric Yang-Mills (SYM) theory is computed using gauge/gravity duality. The results are qualitatively similar to that of synchrotron radiation produced by an electron in circular motion in classical electrodynamics: At large velocities the quark emits radiation in a narrow beam along its velocity vector with a characteristic opening angle α˜1/γ and radial thickness scaling like ˜1/γ3.
Measuring the EOS of a Dense, Strongly Coupled Plasma; Description of the Technique
International Nuclear Information System (INIS)
Benage, John F. Jr.; Kyraka, George; Workman, Jonathan; Tierney, Thomas
1997-08-01
This paper describes a new experimental design which we believe can produce reasonably accurate data for the equation of state (EOS) of a dense plasma. This design takes advantage of the standard shock technique used for determining the high pressure EOS of solids. It also utilizes recently developed experimental techniques for producing dense, strongly coupled plasmas as well as new diagnostic techniques for measuring the properties of these plasmas. The results should be able to distinguish among theoretical models for plasmas at just under solid density and temperatures of 10's of eV
DEFF Research Database (Denmark)
Kuznetsov, A.M.; Ulstrup, Jens
2002-01-01
We present a new view and an analytical formalism of electron flow through a donor-acceptor molecule inserted between a pair of metal electrodes. The donor and acceptor levels are strongly coupled to an environmental nuclear continuum. The formalism applies to molecular donor-acceptor systems both...... in vacuum or air, and in aqueous solution under electrochemical potential control. Multifarious patterns of rectified electron flow from the negatively to the positively biased electrode arise. The electronic interaction between the donor and acceptor fragments, mutually and with the electrodes, can be weak...
Global Behavior for a Strongly Coupled Predator-Prey Model with One Resource and Two Consumers
Directory of Open Access Journals (Sweden)
Yujuan Jiao
2012-01-01
Full Text Available We consider a strongly coupled predator-prey model with one resource and two consumers, in which the first consumer species feeds on the resource according to the Holling II functional response, while the second consumer species feeds on the resource following the Beddington-DeAngelis functional response, and they compete for the common resource. Using the energy estimates and Gagliardo-Nirenberg-type inequalities, the existence and uniform boundedness of global solutions for the model are proved. Meanwhile, the sufficient conditions for global asymptotic stability of the positive equilibrium for this model are given by constructing a Lyapunov function.
Analyzing quantum jumps of one and two atoms strongly coupled to an optical cavity
DEFF Research Database (Denmark)
Reick, Sebastian; Mølmer, Klaus; Alt, Wolfgang
2010-01-01
We induce quantum jumps between the hyperfine ground states of one and two cesium atoms, strongly coupled to the mode of a high-finesse optical resonator, and analyze the resulting random telegraph signals. We identify experimental parameters to deduce the atomic spin state nondestructively from...... time-dependent probabilities for the atoms to be in one of the two hyperfine states. This analysis is extended to short time bins where a simple threshold analysis would not yield reasonable results. We discuss the effect of super-Poissonian photon number distributions caused by atomic motion....
Drag force in strongly coupled, anisotropic plasma at finite chemical potential
Energy Technology Data Exchange (ETDEWEB)
Chakraborty, Somdeb; Haque, Najmul [Theory Division, Saha Institute of Nuclear Physics,1/AF Bidhannagar, Kolkata-700 064 (India)
2014-12-30
We employ methods of gauge/string duality to analyze the drag force on a heavy quark moving through a strongly coupled, anisotropic N=4,SU(N) super Yang-Mills plasma in the presence of a finite U(1) chemical potential. We present numerical results valid for any value of the anisotropy parameter and the U(1) charge density and arbitrary direction of the quark velocity with respect to the direction of anisotropy. In the small anisotropy limit we are also able to furnish analytical results.
Imaginary potential in strongly coupled N = 4 SYM plasma in a magnetic field
Zhang, Zi-qiang; Hou, De-fu
2018-03-01
We study the effect of a constant magnetic field on the imaginary part of a quarkonia potential in a strongly-coupled N = 4 SYM plasma. We consider the pair axis to be aligned perpendicularly and parallel to the magnetic field, respectively. For both cases, we find that the presence of the magnetic field tends to enhance the imaginary potential thus decreasing the thermal width. In addition, the magnetic field has a stronger effect on the imaginary potential when the pair axis is perpendicular to the magnetic field rather than parallel.
International Nuclear Information System (INIS)
Szyniszewski, Marcin; Manchester Univ.; Cichy, Krzysztof; Poznan Univ.; Kujawa-Cichy, Agnieszka
2014-10-01
We employ exact diagonalization with strong coupling expansion to the massless and massive Schwinger model. New results are presented for the ground state energy and scalar mass gap in the massless model, which improve the precision to nearly 10 -9 %. We also investigate the chiral condensate and compare our calculations to previous results available in the literature. Oscillations of the chiral condensate which are present while increasing the expansion order are also studied and are shown to be directly linked to the presence of flux loops in the system.
Viscosity calculated in simulations of strongly coupled dusty plasmas with gas friction
International Nuclear Information System (INIS)
Feng Yan; Goree, J.; Liu Bin
2011-01-01
A two-dimensional strongly coupled dusty plasma is modeled using Langevin and frictionless molecular dynamical simulations. The static viscosity η and the wave-number-dependent viscosity η(k) are calculated from the microscopic shear in the random motion of particles. A recently developed method of calculating the wave-number-dependent viscosity η(k) is validated by comparing the results of η(k) from the two simulations. It is also verified that the Green-Kubo relation can still yield an accurate measure of the static viscosity η in the presence of a modest level of friction as in dusty plasma experiments.
Experimental Measurement of Self-Diffusion in a Strongly Coupled Plasma
2016-08-04
and ni for all the analysis regions are shown with vertical error bars representing the standard deviation . ωp and Γi are calculated from Ti and ni for... standard - deviation uncertainties of the mean values, which we use in the main article to calculate the uncer- tainties in hΔvxðtÞiþ=hΔvxð0Þiþ. The fits to...Areas: Atomic and Molecular Physics, Plasma Physics, Statistical Physics I. INTRODUCTION In strongly coupled plasmas [1], the Coulomb interaction energy
The Bethe roots of Regge cuts in strongly coupled N=4 SYM theory
International Nuclear Information System (INIS)
Bartels, J.; Schomerus, V.; Sprenger, M.
2015-01-01
We describe a general algorithm for the computation of the remainder function for n-gluon scattering in multi-Regge kinematics for strongly coupled planar N=4 super Yang-Mills theory. This regime is accessible through the infrared physics of an auxiliary quantum integrable system describing strings in AdS 5 ×S 5 . Explicit formulas are presented for n=6 and n=7 external gluons. Our results are consistent with expectations from perturbative gauge theory. This paper comprises the technical details for the results announced in http://dx.doi.org/10.1007/JHEP10(2014)067.
Analytic properties of the OCP and ionic mixtures in the strongly coupled fluid state
International Nuclear Information System (INIS)
DeWitt, H.E.
1993-01-01
Exact results for the Madelung constants and first order anharmonic energies are given for the inverse power potentials with the Coulomb potential as the softest example. Similar exact results are obtained using the analysis of Rosenfeld on the Γ → ∞ limit for the OCP internal energy, direct correlation function, screening function, and bridge functions. Knowing these exact limits for the fluid phase of the OCP allows one to determine the nature of the thermal corrections to the strongly coupled results. Solutions of the HNC equation modified with the hard sphere bridge function give an example
Intrinsic kinetics in heavy ion reactions in the strong-coupling limit
Energy Technology Data Exchange (ETDEWEB)
Isaev, P.N. (AN SSSR, Novosibirsk. Inst. Yadernoj Fiziki)
1985-02-01
A quantum statistical description is suggested for the intrinsic kinetics of nuclear systems with a strong coupling between the collective (global) dynamics and intrinsic degrees of freedom (for a double nuclear system in heavy ion reactions and mother nucleus at the descent stage of fission). The influence of the ''memory'' of the system concerning pre-history of the kinetic process on the form of the kinetic equation is studied in detail. It is shown that Markov's regime is realized at practically all evolution stages of the double nuclear system (and, certainly, in fission). The kinetic equation is written and discussed in this regime.
Strongly correlated photons generated by coupling a three- or four-level system to a waveguide
Zheng, Huaixiu; Gauthier, Daniel J.; Baranger, Harold U.
2012-04-01
We study the generation of strongly correlated photons by coupling an atom to photonic quantum fields in a one-dimensional waveguide. Specifically, we consider a three-level or four-level system for the atom. Photon-photon bound states emerge as a manifestation of the strong photon-photon correlation mediated by the atom. Effective repulsive or attractive interaction between photons can be produced, causing either suppressed multiphoton transmission (photon blockade) or enhanced multiphoton transmission (photon-induced tunneling). As a result, nonclassical light sources can be generated on demand by sending coherent states into the proposed system. We calculate the second-order correlation function of the transmitted field and observe bunching and antibunching caused by the bound states. Furthermore, we demonstrate that the proposed system can produce photon pairs with a high degree of spectral entanglement, which have a large capacity for carrying information and are important for large-alphabet quantum communication.
Strong coupling operation of a free-electron-laser amplifier with an axial magnetic field
Energy Technology Data Exchange (ETDEWEB)
Rullier, J.L.; Devin, A.; Gardelle, J.; Labrouche, J.; Le Taillandier, P. [Commissariat a lEnergie Atomique, Boite Postale 2, 33114 Le Barp (France); Donohue, J.T. [Centre dEtudes Nucleaires de Bordeaux-Gradignan, Boite Postale 120, 33175 Gradignan (France)
1996-03-01
We present the results of a free-electron-laser (FEL) experiment at 35 GHz, using a strongly relativistic electron beam ({ital T}=1.75 MeV). The electron pulse length is 30 ns full width at half maximum with a peak current of 400 A. The FEL is designed to operate in the high-gain Compton regime, with a negative coupling parameter ({Phi}{lt}0) leading to a strong growth rate. More than 50 MW of rf power in the TE{sub 1}{sub 1} mode (43 dB gain) has been obtained with good reproducibility. The experimental results are in good agreement with predictions made using the three-dimensional stationary simulation code solitude. {copyright} {ital 1996 The American Physical Society.}
Feng, Yan; Lin, Wei; Murillo, M S
2017-11-01
Transport properties of two-dimensional (2D) strongly coupled dusty plasmas have been investigated in detail, but never for viscosity with a strong perpendicular magnetic field; here, we examine this scenario using Langevin dynamics simulations of 2D liquids with a binary Yukawa interparticle interaction. The shear viscosity η of 2D liquid dusty plasma is estimated from the simulation data using the Green-Kubo relation, which is the integration of the shear stress autocorrelation function. It is found that, when a perpendicular magnetic field is applied, the shear viscosity of 2D liquid dusty plasma is modified substantially. When the magnetic field is increased, its viscosity increases at low temperatures, while at high temperatures its viscosity diminishes. It is determined that these different variational trends of η arise from the different behaviors of the kinetic and potential parts of the shear stress under external magnetic fields.
Effective action for superfluid Fermi systems in the strong-coupling limit
International Nuclear Information System (INIS)
Dupuis, N.
2005-01-01
We derive the low-energy effective action for three-dimensional superfluid Fermi systems in the strong-coupling limit, where superfluidity originates from Bose-Einstein condensation of composite bosons. Taking into account density and pairing fluctuations on the same footing, we show that the effective action involves only the fermion density ρ r and its conjugate variable, the phase θ r of the pairing order parameter Δ r . We recover the standard action of a Bose superfluid of density ρ r /2, where the bosons have a mass m B =2m and interact via a repulsive contact potential with amplitude g B =4πa B /m B ,a B =2a (a the s-wave scattering length associated to the fermion-fermion interaction in vacuum). For lattice models, the derivation of the effective action is based on the mapping of the attractive Hubbard model onto the Heisenberg model in a uniform magnetic field, and a coherent state path integral representation of the partition function. The effective description of the Fermi superfluid in the strong-coupling limit is a Bose-Hubbard model with an intersite hopping amplitude t B =J/2 and an on-site repulsive interaction U B =2Jz, where J=4t 2 /U (t and -U are the intersite hopping amplitude and the on-site attraction in the (fermionic) Hubbard model, z the number of nearest-neighbor sites)
Effective action for superfluid Fermi systems in the strong-coupling limit
Dupuis, N.
2005-07-01
We derive the low-energy effective action for three-dimensional superfluid Fermi systems in the strong-coupling limit, where superfluidity originates from Bose-Einstein condensation of composite bosons. Taking into account density and pairing fluctuations on the same footing, we show that the effective action involves only the fermion density ρr and its conjugate variable, the phase θr of the pairing order parameter Δr . We recover the standard action of a Bose superfluid of density ρr/2 , where the bosons have a mass mB=2m and interact via a repulsive contact potential with amplitude gB=4πaB/mB,aB=2a ( a the s -wave scattering length associated to the fermion-fermion interaction in vacuum). For lattice models, the derivation of the effective action is based on the mapping of the attractive Hubbard model onto the Heisenberg model in a uniform magnetic field, and a coherent state path integral representation of the partition function. The effective description of the Fermi superfluid in the strong-coupling limit is a Bose-Hubbard model with an intersite hopping amplitude tB=J/2 and an on-site repulsive interaction UB=2Jz , where J=4t2/U ( t and -U are the intersite hopping amplitude and the on-site attraction in the (fermionic) Hubbard model, z the number of nearest-neighbor sites).
The shot noise of a strongly correlated quantum dot coupled to the Luttinger liquid leads
International Nuclear Information System (INIS)
Yang, Kai-Hua; He, Xian; Wang, Huai-Yu; Liu, Kai-Di; Liu, Bei-Yun
2014-01-01
We study the shot noise of a strongly correlated quantum dot weakly coupled to Luttinger liquid leads in the Kondo regime by means of the extended equation of motion method. A general zero-frequency shot noise formula with good convergence is derived. The shot noise exhibits a non-monotonic dependence on voltage for weak intralead interaction. There is a peak around the Kondo temperature at low voltage when the interaction is very weak, and its height decreases rapidly with the intralead interaction increasing. When the interaction is moderately strong the peak disappears and the shot noise scales as a power law in bias voltage, indicating that the intralead electron interaction suppresses the shot noise. It is possible that the measurements of the shot noise spectrum can extract the information of the intralead interaction. - Highlights: • The shot noise of a dot coupled to Luttinger liquid leads in the Kondo regime. • A shot noise formula is derived. • Intralead interaction suppresses the shot noise. • The noise shows different voltage-dependence for different intralead interaction
Strong coupling of a single photon to a superconducting qubit using circuit quantum electrodynamics.
Wallraff, A; Schuster, D I; Blais, A; Frunzio, L; Huang, R- S; Majer, J; Kumar, S; Girvin, S M; Schoelkopf, R J
2004-09-09
The interaction of matter and light is one of the fundamental processes occurring in nature, and its most elementary form is realized when a single atom interacts with a single photon. Reaching this regime has been a major focus of research in atomic physics and quantum optics for several decades and has generated the field of cavity quantum electrodynamics. Here we perform an experiment in which a superconducting two-level system, playing the role of an artificial atom, is coupled to an on-chip cavity consisting of a superconducting transmission line resonator. We show that the strong coupling regime can be attained in a solid-state system, and we experimentally observe the coherent interaction of a superconducting two-level system with a single microwave photon. The concept of circuit quantum electrodynamics opens many new possibilities for studying the strong interaction of light and matter. This system can also be exploited for quantum information processing and quantum communication and may lead to new approaches for single photon generation and detection.
On Yang--Mills Theories with Chiral Matter at Strong Coupling
Energy Technology Data Exchange (ETDEWEB)
Shifman, M.; /Minnesota U., Theor. Phys. Inst. /Saclay, SPhT; Unsal, Mithat; /SLAC /Stanford U., Phys. Dept.
2008-08-20
Strong coupling dynamics of Yang-Mills theories with chiral fermion content remained largely elusive despite much effort over the years. In this work, we propose a dynamical framework in which we can address non-perturbative properties of chiral, non-supersymmetric gauge theories, in particular, chiral quiver theories on S{sub 1} x R{sub 3}. Double-trace deformations are used to stabilize the center-symmetric vacuum. This allows one to smoothly connect smaller(S{sub 1}) to larger(S{sub 1}) physics (R{sub 4} is the limiting case) where the double-trace deformations are switched off. In particular, occurrence of the mass gap in the gauge sector and linear confinement due to bions are analytically demonstrated. We find the pattern of the chiral symmetry realization which depends on the structure of the ring operators, a novel class of topological excitations. The deformed chiral theory, unlike the undeformed one, satisfies volume independence down to arbitrarily small volumes (a working Eguchi-Kawai reduction) in the large N limit. This equivalence, may open new perspectives on strong coupling chiral gauge theories on R{sub 4}.
Energy Technology Data Exchange (ETDEWEB)
Takamoto, Makoto [Department of Earth and Planetary Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033 (Japan); Lazarian, Alexandre, E-mail: mtakamoto@eps.s.u-tokyo.ac.jp, E-mail: alazarian@facstaff.wisc.edu [Department of Astronomy, University of Wisconsin, 475 North Charter Street, Madison, WI 53706 (United States)
2016-11-10
In this Letter, we report compressible mode effects on relativistic magnetohydrodynamic (RMHD) turbulence in Poynting-dominated plasmas using three-dimensional numerical simulations. We decomposed fluctuations in the turbulence into 3 MHD modes (fast, slow, and Alfvén) following the procedure of mode decomposition in Cho and Lazarian, and analyzed their energy spectra and structure functions separately. We also analyzed the ratio of compressible mode to Alfvén mode energy with respect to its Mach number. We found the ratio of compressible mode increases not only with the Alfvén Mach number, but also with the background magnetization, which indicates a strong coupling between the fast and Alfvén modes. It also signifies the appearance of a new regime of RMHD turbulence in Poynting-dominated plasmas where the fast and Alfvén modes are strongly coupled and, unlike the non-relativistic MHD regime, cannot be treated separately. This finding will affect particle acceleration efficiency obtained by assuming Alfvénic critical-balance turbulence and can change the resulting photon spectra emitted by non-thermal electrons.
Continuum Lowering and Fermi-Surface Rising in Strongly Coupled and Degenerate Plasmas
Hu, S. X.
2017-08-01
Continuum lowering is a well known and important physics concept that describes the ionization potential depression (IPD) in plasmas caused by thermal- or pressure-induced ionization of outer-shell electrons. The existing IPD models are often used to characterize plasma conditions and to gauge opacity calculations. Recent precision measurements have revealed deficits in our understanding of continuum lowering in dense hot plasmas. However, these investigations have so far been limited to IPD in strongly coupled but nondegenerate plasmas. Here, we report a first-principles study of the K -edge shifting in both strongly coupled and fully degenerate carbon plasmas, with quantum molecular dynamics calculations based on the all-electron density-functional theory. The resulting K -edge shifting versus plasma density, as a probe to the continuum lowering and the Fermi-surface rising, is found to be significantly different from predictions of existing IPD models. In contrast, a simple model of "single-atom-in-box," developed in this work, accurately predicts K -edge locations as ab initio calculations provide.
Heavy quark energy loss far from equilibrium in a strongly coupled collision
Chesler, Paul M; Rajagopal, Krishna
2013-01-01
We compute and study the drag force acting on a heavy quark propagating through the matter produced in the collision of two sheets of energy in a strongly coupled gauge theory that can be analyzed holographically. Although this matter is initially far from equilibrium, we find that the equilibrium expression for heavy quark energy loss in a homogeneous strongly coupled plasma with the same instantaneous energy density or pressure as that at the location of the quark describes many qualitative features of our results. One interesting exception is that there is a time delay after the initial collision before the heavy quark energy loss becomes significant. At later times, once a liquid plasma described by viscous hydrodynamics has formed, expressions based upon assuming instantaneous homogeneity and equilibrium provide a semi-quantitative description of our results - as long as the rapidity of the heavy quark is not too large. For a heavy quark with large rapidity, the gradients in the velocity of the hydrodyna...
Infrared exponents and the strong-coupling limit in lattice Landau gauge
International Nuclear Information System (INIS)
Sternbeck, Andre; Smekal, Lorenz von
2010-01-01
We study the gluon and ghost propagators of lattice Landau gauge in the strong-coupling limit β=0 in pure SU(2) lattice gauge theory to find evidence of the conformal infrared behavior of these propagators as predicted by a variety of functional continuum methods for asymptotically small momenta q 2 QCD 2 . In the strong-coupling limit, this same behavior is obtained for the larger values of a 2 q 2 (in units of the lattice spacing a), where it is otherwise swamped by the gauge-field dynamics. Deviations for a 2 q 2 <1 are well parameterized by a transverse gluon mass ∝1/a. Perhaps unexpectedly, these deviations are thus no finite-volume effect but persist in the infinite-volume limit. They furthermore depend on the definition of gauge fields on the lattice, while the asymptotic conformal behavior does not. We also comment on a misinterpretation of our results by Cucchieri and Mendes (Phys. Rev. D 81:016005, 2010). (orig.)
Munson, C P; Taylor, A J; Trainor, R J; Wood, B P; Wysocki, F J
1999-01-01
Summary form only given. Atlas is a high current (~30 MA peak, with a current risetime ~4.5 mu sec), high energy (E/sub stored/=24 MJ, E /sub load/=3-6 MJ), pulsed power facility which is being constructed at Los Alamos National Laboratory with a scheduled completion date in the year 2000. When operational, this facility will provide a platform for experiments in high pressure shocks (>20 Mbar), adiabatic compression ( rho / rho /sub 0/>5, P>10 Mbar), high magnetic fields (~2000 T), high strain and strain rates ( epsilon >200, d epsilon /dt~10/sup 4/ to 10/sup 6/ s/sup -1/), hydrodynamic instabilities of materials in turbulent regimes, magnetized target fusion, equation of state, and strongly coupled plasmas. For the strongly coupled plasma experiments, an auxiliary capacitor bank will be used to generate a moderate density (<0.1 solid), relatively cold (~1 eV) plasma by ohmic heating of a conducting material of interest such as titanium. This target plasma will be compressed against a central column conta...
Chahid, M
2000-01-01
The purpose of the present work is a quantitative study of the spin time relaxation within superweak ferrimagnetic materials exhibiting a paramagnetic-ferrimagnetic transition, when the temperature is changed from an initial value T sub i to a final one T sub f very close to the critical temperature T sub c. From a magnetic point of view, the material under investigation is considered to be made of two strongly coupled paramagnetic sublattices of respective moments phi (cursive,open) Greek and psi. Calculations are made within a Landau mean-field theory, whose free energy involves, in addition to quadratic and quartic terms in both moments phi (cursive,open) Greek and psi, a lowest-order coupling - Cphi (cursive,open) Greek psi, where C<0 stands for the coupling constant measuring the interaction between the two sublattices. We first determine the time dependence of the shifts of the order parameters delta phi (cursive,open) Greek and delta psi from the equilibrium state. We find that this time dependence ...
International Nuclear Information System (INIS)
Gelis, Francois; Venugopalan, Raju
2006-01-01
We develop a formalism for particle production in a field theory coupled to a strong time-dependent external source. An example of such a theory is the color glass condensate. We derive a formula, in terms of cut vacuum-vacuum Feynman graphs, for the probability of producing a given number of particles. This formula is valid to all orders in the coupling constant. The distribution of multiplicities is non-Poissonian, even in the classical approximation. We investigate an alternative method of calculating the mean multiplicity. At leading order, the average multiplicity can be expressed in terms of retarded solutions of classical equations of motion. We demonstrate that the average multiplicity at next-to-leading order can be formulated as an initial value problem by solving equations of motion for small fluctuation fields with retarded boundary conditions. The variance of the distribution can be calculated in a similar fashion. Our formalism therefore provides a framework to compute from first principles particle production in proton-nucleus and nucleus-nucleus collisions beyond leading order in the coupling constant and to all orders in the source density. We also provide a transparent interpretation (in conventional field theory language) of the well-known Abramovsky-Gribov-Kancheli (AGK) cancellations. Explicit connections are made between the framework for multi-particle production developed here and the framework of reggeon field theory
Small scale demand type neon liquefaction plant
Dube, W. P.; Slifka, A. J.; Bitsy, R. M.; Sparks, L. L.; Johnson, K. B.
Low-temperature measurement of the thermal conductivity of insulating materials is generally made using a boil-off calorimetry technique involving liquid hydrogen (LH2). Liquid neon (LNe) has nearly the same normal boiling point as LH2, but has a much larger heat of vaporization, allowing extended run times. The main drawback of using LNe has been its excessive cost; $170.00 versus $1.50/l for LH2 (1989 prices). A neon liquefaction plant has been designed and constructed to capture, purify, and refrigerate the neon boil-off from calorimetry experiments. Recycling the neon reduces operating costs to approximately $20/l. The system consists of a purification section, a heat exchanger, LNe and LH2 storage dewars, and a fully automated control system. After purification, neon is liquified in the heat exchanger by LH2 flowing countercurrently through stainless steel cooling coils. Hydrogen flow is automatically adjusted to keep the neon at its normal saturation temperature, 27 K. The liquid neon is then stored in a dewar placed directly below the heat exchanger.
Routine daily physical activity and glucose variations are strongly coupled in adults with T1DM.
Farabi, Sarah S; Carley, David W; Cinar, Ali; Quinn, Lauretta
2015-12-01
Type 1 Diabetes (T1DM) is characterized by altered glucose homeostasis resulting in wide glucose variations throughout a 24-h period. The relationship between routine daily physical activity and glucose variations has not been systematically investigated in adults with T1DM. The objectives of this study were to characterize and quantify the relationship between routine daily activity and glucose variations in a small group of adults with T1DM. Adults with T1DM treated with an insulin pump were recruited for the study. Over a 3-day period, glucose variations were monitored with a continuous glucose monitoring system (CGMS) and routine daily physical activity was assessed using an accelerometer-based physical activity-monitoring band. Simultaneous glucose and physical activity data for one 24-h period were used for analysis. Cross-correlation function and wavelet coherence analyses were employed to quantify the coupling between physical activity and glucose. Twelve subjects were included in the analysis. Cross-correlation function analysis revealed strong coupling between activity and glucose. Wavelet Coherence demonstrated that slower oscillations (120-340 min) of glucose and physical activity exhibited significantly greater coherence (F = 12.6, P < 0.0001) than faster oscillations (10 and 120 min). Physical activity and glucose demonstrate strong time and frequency-dependent coupling throughout a 24-h time period in adults with T1DM. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.
Conner, Kyle M; Arostegui, AnnaMaria C; Swanson, Daniel D; Brown, Seth N
2018-03-08
The 2,2'-biphenylene-bridged bis(iminosemiquinone) complexes ( t BuClip)M [ t BuClipH 4 = 4,4'-di- tert-butyl- N, N'-bis(3,5-di- tert-butyl-2-hydroxyphenyl)-2,2'-diaminobiphenyl; M = Pd, Pt] can be reduced to the bis(aminophenoxide) complexes ( t BuClipH 2 )M by reaction with hydrazobenzene (M = Pd) or by catalytic hydrogenation (M = Pt). The palladium complex with one aminophenoxide ligand and one iminosemiquinone ligand, ( t BuClipH)Pd, is generated by comproportionation of ( t BuClip)Pd with ( t BuClipH 2 )Pd in a process that is both slow (0.06 M -1 s -1 in toluene at 23 °C) and only modestly favorable ( K com = 1.9 in CDCl 3 ), indicating that both N-H bonds have essentially the same bond strength. The mono(iminoquinone) complex ( t BuClipH)Pt has not been observed, indicating that the platinum analogue shows no tendency to comproportionate ( K com < 0.1). The average bond dissociation free energies (BDFE) of the complexes have been established by equilibration with suitably substituted hydrazobenzenes, and the palladium bis(iminosemiquinone) is markedly more oxidizing than the platinum compound, with hydrogen transfer from ( t BuClipH 2 )Pt to ( t BuClip)Pd occurring with Δ G° = -8.9 kcal mol -1 . The palladium complex ( t BuClipH 2 )Pd reacts with nitroxyl radicals in two observable steps, with the first hydrogen transfer taking place slightly faster than the second. In the platinum analogue, the first hydrogen transfer is much slower than the second, presumably because the N-H bond in the monoradical complex ( t BuClipH)Pt is unusually weak. Using driving force-rate correlations, it is estimated that this bond has a BDFE of 55.1 kcal mol -1 , which is 7.1 kcal mol -1 weaker than that of the first N-H bond in ( t BuClipH 2 )Pt. The two radical centers in the platinum, but not the palladium, complex thus act in concert with each other and display a strong thermodynamic bias toward two-electron reactivity. The greater thermodynamic and kinetic coupling in
Strong dispersive coupling of a high-finesse cavity to a micromechanical membrane.
Thompson, J D; Zwickl, B M; Jayich, A M; Marquardt, Florian; Girvin, S M; Harris, J G E
2008-03-06
Macroscopic mechanical objects and electromagnetic degrees of freedom can couple to each other through radiation pressure. Optomechanical systems in which this coupling is sufficiently strong are predicted to show quantum effects and are a topic of considerable interest. Devices in this regime would offer new types of control over the quantum state of both light and matter, and would provide a new arena in which to explore the boundary between quantum and classical physics. Experiments so far have achieved sufficient optomechanical coupling to laser-cool mechanical devices, but have not yet reached the quantum regime. The outstanding technical challenge in this field is integrating sensitive micromechanical elements (which must be small, light and flexible) into high-finesse cavities (which are typically rigid and massive) without compromising the mechanical or optical properties of either. A second, and more fundamental, challenge is to read out the mechanical element's energy eigenstate. Displacement measurements (no matter how sensitive) cannot determine an oscillator's energy eigenstate, and measurements coupling to quantities other than displacement have been difficult to realize in practice. Here we present an optomechanical system that has the potential to resolve both of these challenges. We demonstrate a cavity which is detuned by the motion of a 50-nm-thick dielectric membrane placed between two macroscopic, rigid, high-finesse mirrors. This approach segregates optical and mechanical functionality to physically distinct structures and avoids compromising either. It also allows for direct measurement of the square of the membrane's displacement, and thus in principle the membrane's energy eigenstate. We estimate that it should be practical to use this scheme to observe quantum jumps of a mechanical system, an important goal in the field of quantum measurement.
Flickering light a history of neon
Ribbat, Christoph
2013-01-01
Without neon, Las Vegas might still be a sleepy desert town in Nevada and Times Square merely another busy intersection in New York City. Transformed by the installation of these brightly colored signs, these destinations are now world-famous, representing the vibrant heart of popular culture. But for some, neon lighting represents the worst of commercialism. Energized by the conflicting love and hatred people have for neon, Flickering Light explores its technological and intellectual history, from the discovery of the noble gas in late nineteenth-century London to its fading popul
Optical investigation of the strong spin-orbit-coupled magnetic semimetal YbMnBi2
Chaudhuri, Dipanjan; Cheng, Bing; Yaresko, Alexander; Gibson, Quinn D.; Cava, R. J.; Armitage, N. P.
2017-08-01
Strong spin-orbit coupling (SOC) can result in ground states with nontrivial topological properties. The situation is even richer in magnetic systems where the magnetic ordering can potentially have strong influence over the electronic band structure. The class of A MnBi2 (A = Sr, Ca) compounds are important in this context as they are known to host massive Dirac fermions with strongly anisotropic dispersion, which is believed to be due to the interplay between strong SOC and magnetic degrees of freedom. We report the optical conductivity of YbMnBi2, a newly discovered member of this family and a proposed Weyl semimetal (WSM) candidate with broken time reversal symmetry. Together with density functional theory (DFT) band-structure calculations, we show that the complex conductivity can be interpreted as the sum of an intraband Drude response and interband transitions. We argue that the canting of the magnetic moments that has been proposed to be essential for the realization of the WSM in an otherwise antiferromagnetically ordered system is not necessary to explain the optical conductivity. We believe our data is explained qualitatively by the uncanted magnetic structure with a small offset of the chemical potential from strict stochiometry. We find no definitive evidence of a bulk Weyl nodes. Instead, we see signatures of a gapped Dirac dispersion, common in other members of A MnBi2 family or compounds with similar 2D network of Bi atoms. We speculate that the evidence for a WSM seen in ARPES arises through a surface magnetic phase. Such an assumption reconciles all known experimental data.
Energy Technology Data Exchange (ETDEWEB)
Weymann, Ireneusz, E-mail: weymann@amu.edu.pl [Faculty of Physics, Adam Mickiewicz University, 61-614 Poznań (Poland)
2015-05-07
We analyze the spin-dependent linear-response transport properties of double quantum dots strongly coupled to external ferromagnetic leads. By using the numerical renormalization group method, we determine the dependence of the linear conductance and tunnel magnetoresistance on the degree of spin polarization of the leads and the position of the double dot levels. We focus on the transport regime where the system exhibits the SU(4) Kondo effect. It is shown that the presence of ferromagnets generally leads the suppression of the linear conductance due to the presence of an exchange field. Moreover, the exchange field gives rise to a transition from the SU(4) to the orbital SU(2) Kondo effect. We also analyze the dependence of the tunnel magnetoresistance on the double dot levels' positions and show that it exhibits a very nontrivial behavior.
Strong correlation between early stage atherosclerosis and electromechanical coupling of aorta
Liu, X. Y.; Yan, F.; Niu, L. L.; Chen, Q. N.; Zheng, H. R.; Li, J. Y.
2016-03-01
Atherosclerosis is the underlying cause of cardiovascular diseases that are responsible for many deaths in the world, and the early diagnosis of atherosclerosis is highly desirable. The existing imaging methods, however, are not capable of detecting the early stage of atherosclerosis development due to their limited spatial resolution. Using piezoresponse force microscopy (PFM), we show that the piezoelectric response of an aortic wall increases as atherosclerosis advances, while the stiffness of the aorta shows a less evident correlation with atherosclerosis. Furthermore, we show that there is strong correlation between the coercive electric field necessary to switch the polarity of the artery and the development of atherosclerosis. Thus by measuring the electromechanical coupling of the aortic wall, it is possible to probe atherosclerosis at the early stage of its development, not only improving the spatial resolution by orders of magnitude, but also providing comprehensive quantitative information on the biomechanical properties of the artery.
Field-theoretic Methods in Strongly-Coupled Models of General Gauge Mediation
Fortin, Jean-Francois
2013-01-01
An often-exploited feature of the operator product expansion (OPE) is that it incorporates a splitting of ultraviolet and infrared physics. In this paper we use this feature of the OPE to perform simple, approximate computations of soft masses in gauge-mediated supersymmetry breaking. The approximation amounts to truncating the OPEs for hidden-sector current-current operator products. Our method yields visible-sector superpartner spectra in terms of vacuum expectation values of a few hidden-sector IR elementary fields. We manage to obtain reasonable approximations to soft masses, even when the hidden sector is strongly coupled. We demonstrate our techniques in several examples, including a new framework where supersymmetry-breaking arises both from a hidden sector and dynamically.
Room temperature strong coupling effects from single ZnO nanowire microcavity
Das, Ayan
2012-05-01
Strong coupling effects in a dielectric microcavity with a single ZnO nanowire embedded in it have been investigated at room temperature. A large Rabi splitting of ?100 meV is obtained from the polariton dispersion and a non-linearity in the polariton emission characteristics is observed at room temperature with a low threshold of 1.63 ?J/cm2, which corresponds to a polariton density an order of magnitude smaller than that for the Mott transition. The momentum distribution of the lower polaritons shows evidence of dynamic condensation and the absence of a relaxation bottleneck. The polariton relaxation dynamics were investigated by timeresolved measurements, which showed a progressive decrease in the polariton relaxation time with increase in polariton density. © 2012 Optical Society of America.
Violation of the Holographic Viscosity Bound in a Strongly Coupled Anisotropic Plasma
Rebhan, Anton; Steineder, Dominik
2012-01-01
We study the conductivity and shear viscosity tensors of a strongly coupled N=4 super-Yang-Mills plasma which is kept anisotropic by a θ parameter that depends linearly on one of the spatial dimensions. Its holographic dual is given by an anisotropic axion-dilaton-gravity background and has recently been proposed by Mateos and Trancanelli as a model for the preequilibrium stage of quark-gluon plasma in heavy-ion collisions. By applying the membrane paradigm which we also check by numerical evaluation of Kubo formula and lowest lying quasinormal modes, we find that the shear viscosity purely transverse to the direction of anisotropy saturates the holographic viscosity bound, whereas longitudinal shear viscosities are smaller, providing the first such example not involving higher-derivative theories of gravity and, more importantly, with fully known gauge-gravity correspondence.
Emori, Satoru; Gray, Benjamin A; Jeon, Hyung-Min; Peoples, Joseph; Schmitt, Maxwell; Mahalingam, Krishnamurthy; Hill, Madelyn; McConney, Michael E; Gray, Matthew T; Alaan, Urusa S; Bornstein, Alexander C; Shafer, Padraic; N'Diaye, Alpha T; Arenholz, Elke; Haugstad, Greg; Meng, Keng-Yuan; Yang, Fengyuan; Li, Dongyao; Mahat, Sushant; Cahill, David G; Dhagat, Pallavi; Jander, Albrecht; Sun, Nian X; Suzuki, Yuri; Howe, Brandon M
2017-09-01
Low-loss magnetization dynamics and strong magnetoelastic coupling are generally mutually exclusive properties due to opposing dependencies on spin-orbit interactions. So far, the lack of low-damping, magnetostrictive ferrite films has hindered the development of power-efficient magnetoelectric and acoustic spintronic devices. Here, magnetically soft epitaxial spinel NiZnAl-ferrite thin films with an unusually low Gilbert damping parameter (ferrite. At the same time, the coherently strained film structure suppresses extrinsic damping, enables soft magnetic behavior, and generates large easy-plane magnetoelastic anisotropy. These findings provide a foundation for a new class of low-loss, magnetoelastic thin film materials that are promising for spin-mechanical devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Directory of Open Access Journals (Sweden)
Yucel Yildirim
2011-09-01
Full Text Available A generic theory of the quasiparticle superconducting gap in underdoped cuprates is derived in the strong-coupling limit, and found to describe the experimental “second gap” in absolute scale. In drastic contrast to the standard pairing gap associated with Bogoliubov quasiparticle excitations, the quasiparticle gap is shown to originate from anomalous kinetic (scattering processes, with a size unrelated to the pairing strength. Consequently, the k dependence of the gap deviates significantly from the pure d_{x^{2}-y^{2}} wave of the order parameter. Our study reveals a new paradigm for the nature of the superconducting gap, and is expected to reconcile numerous apparent contradictions among existing experiments and point toward a more coherent understanding of high-temperature superconductivity.
Observation of dust acoustic shock wave in a strongly coupled dusty plasma
International Nuclear Information System (INIS)
Sharma, Sumita K.; Boruah, A.; Nakamura, Y.; Bailung, H.
2016-01-01
Dust acoustic shock wave is observed in a strongly coupled laboratory dusty plasma. A supersonic flow of charged microparticles is allowed to perturb a stationary dust fluid to excite dust acoustic shock wave. The evolution process beginning with steepening of initial wave front and then formation of a stable shock structure is similar to the numerical results of the Korteweg-de Vries-Burgers equation. The measured Mach number of the observed shock wave agrees with the theoretical results. Reduction of shock amplitude at large distances is also observed due to the dust neutral collision and viscosity effects. The dispersion relation and the spatial damping of a linear dust acoustic wave are also measured and compared with the relevant theory.
Strong Bulk-Edge Coupling in the Compressible Half-Filled Quantum Hall State
International Nuclear Information System (INIS)
Milovanovic, M.V.; Shimshoni, E.
1999-01-01
We studied analytically static correlators in the compressible half-filled quantum Hall state, which characterize the nature of charged excitations in the bulk and on the edge of the system. We employ a modified version of the plasma analogy - namely, a mapping to a classical two-dimensional system of interacting particles - similarly to what has been done in studies of the incompressible (Laughlin) states. However, the 'fake plasma' corresponding to the half-filled state is found to have anomalously weak screening properties. As a consequence, the correlations along the edge do not decay algebraically as in the incompressible case, thus indicating the breakdown of Wen's edge theory. On the other hand, the bulk correlator (which parallels the Girvin-MacDonald algebraic off-diagonal long range order) decays algebraically in a similar way as in the incompressible states, signifying the presence of some kind of bosonic order even in the compressible state. The above results suggest that due to the strong coupling between charged modes on the edge and the neutral Fermions (dipoles) in the bulk, the (attractive) correlation hole is not well defined on the edge. Hence, the system there can be modeled as a free Fermi gas of electrons (with an appropriate boundary condition). A possible experimental indication of a strong bulk-edge coupling at half-filling has been indeed observed in non-local resistance measurements [1]. We also suggest, that while our results contradict the validity of an effective one-dimensional description of the edge excitations on the static level, the dynamics may decouple the edge and bulk so as to recover the Laughlin-like behavior apparent in the experiment of Grayson et al
Liu, Peter Q.; Luxmoore, Isaac J.; Mikhailov, Sergey A.; Savostianova, Nadja A.; Valmorra, Federico; Faist, Jérôme; Nash, Geoffrey R.
2015-01-01
Metamaterials and plasmonics are powerful tools for unconventional manipulation and harnessing of light. Metamaterials can be engineered to possess intriguing properties lacking in natural materials, such as negative refractive index. Plasmonics offers capabilities of confining light in subwavelength dimensions and enhancing light–matter interactions. Recently, the technological potential of graphene-based plasmonics has been recognized as the latter features large tunability, higher field-confinement and lower loss compared with metal-based plasmonics. Here, we introduce hybrid structures comprising graphene plasmonic resonators coupled to conventional split-ring resonators, thus demonstrating a type of highly tunable metamaterial, where the interaction between the two resonances reaches the strong-coupling regime. Such hybrid metamaterials are employed as high-speed THz modulators, exhibiting ∼60% transmission modulation and operating speed in excess of 40 MHz. This device concept also provides a platform for exploring cavity-enhanced light–matter interactions and optical processes in graphene plasmonic structures for applications including sensing, photo-detection and nonlinear frequency generation. PMID:26584781
Radiation by a heavy quark in N=4 SYM at strong coupling
Hatta, Y; Mueller, A H; Triantafyllopoulos, D N
2011-01-01
Using the AdS/CFT correspondence in the supergravity approximation, we compute the energy density radiated by a heavy quark undergoing some arbitrary motion in the vacuum of the strongly coupled N=4 supersymmetric Yang-Mills theory. We find that this energy is fully generated via backreaction from the near-boundary endpoint of the dual string attached to the heavy quark. Because of that, the energy distribution shows the same space-time localization as the classical radiation that would be produced by the heavy quark at weak coupling. We believe that this and some other unnatural features of our result (like its anisotropy and the presence of regions with negative energy density) are artifacts of the supergravity approximation, which will be corrected after including string fluctuations. For the case where the quark trajectory is bounded, we also compute the radiated power, by integrating the energy density over the surface of a sphere at infinity. For sufficiently large times, we find agreement with a previo...
Crossover from weak to strong coupling superconductivity in multi-band systems
Energy Technology Data Exchange (ETDEWEB)
Dinola Neto, Francisco [Instituto de Fisica, Universidade Federal Fluminense, Campus da Praia Vermelha, Niteroi, RJ, 24.210-340 (Brazil); Continentino, Mucio A [Centro Brasileiro de Pesquisas FIsicas, Rua Dr Xavier Sigaud, 150-Urca, Rio de Janeiro, RJ, 22290-180 (Brazil); Lacroix, Claudine, E-mail: claudine.lacroix@grenoble.cnrs.f [Institut Neel, CNRS-UJF, 25 avenue des Martyrs, BP 166, 38042 Grenoble Cedex 9 (France)
2010-02-24
The study of superconductivity in correlated systems is an exciting area of condensed matter physics. In this paper we consider superconducting ground states in systems described by two-band models with different effective masses. These two bands are coupled through an effective hybridization that can be directly tuned by pressure. We consider the cases of s-wave superconductivity associated with the electrons in a narrow band and also with inter-band pairing. To study the system in the strong coupling regime we introduce the s-wave scattering length a{sub s}, and obtain the superconducting order parameters and the chemical potential as functions of the interaction strength 1/k{sub F}a{sub s} along the BCS-BEC crossover at T = 0. Finally, we discuss the phase diagram of this model as a function of external pressure and how our results can be applied for two-band systems as Fe pnictides or heavy fermions. The main result of this study is the occurrence of a superconducting quantum critical point (SQCP) in this two-band model.
Liu, Peter Q.; Luxmoore, Isaac J.; Mikhailov, Sergey A.; Savostianova, Nadja A.; Valmorra, Federico; Faist, Jérôme; Nash, Geoffrey R.
2015-11-01
Metamaterials and plasmonics are powerful tools for unconventional manipulation and harnessing of light. Metamaterials can be engineered to possess intriguing properties lacking in natural materials, such as negative refractive index. Plasmonics offers capabilities of confining light in subwavelength dimensions and enhancing light-matter interactions. Recently, the technological potential of graphene-based plasmonics has been recognized as the latter features large tunability, higher field-confinement and lower loss compared with metal-based plasmonics. Here, we introduce hybrid structures comprising graphene plasmonic resonators coupled to conventional split-ring resonators, thus demonstrating a type of highly tunable metamaterial, where the interaction between the two resonances reaches the strong-coupling regime. Such hybrid metamaterials are employed as high-speed THz modulators, exhibiting ~60% transmission modulation and operating speed in excess of 40 MHz. This device concept also provides a platform for exploring cavity-enhanced light-matter interactions and optical processes in graphene plasmonic structures for applications including sensing, photo-detection and nonlinear frequency generation.
Lasing by driven atoms-cavity system in collective strong coupling regime.
Sawant, Rahul; Rangwala, S A
2017-09-12
The interaction of laser cooled atoms with resonant light is determined by the natural linewidth of the excited state. An optical cavity is another optically resonant system where the loss from the cavity determines the resonant optical response of the system. The near resonant combination of an optical Fabry-Pérot cavity with laser cooled and trapped atoms couples two distinct optical resonators via light and has great potential for precision measurements and the creation of versatile quantum optics systems. Here we show how driven magneto-optically trapped atoms in collective strong coupling regime with the cavity leads to lasing at a frequency red detuned from the atomic transition. Lasing is demonstrated experimentally by the observation of a lasing threshold accompanied by polarization and spatial mode purity, and line-narrowing in the outcoupled light. Spontaneous emission into the cavity mode by the driven atoms stimulates lasing action, which is capable of operating as a continuous wave laser in steady state, without a seed laser. The system is modeled theoretically, and qualitative agreement with experimentally observed lasing is seen. Our result opens up a range of new measurement possibilities with this system.
On the absence of pentaquark states from dynamics in strongly coupled lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Anjos, Petrus Henrique Ribeiro dos [Universidade Federal de Goias (UFG), Goiania, GO (Brazil); Veiga, Paulo Afonso Faria da; O' Carroll, Michael [Universidade de Sao Paulo (USP), SP (Brazil); Francisco Neto, Antonio [Universidade Federal de Ouro Preto (UFOP), MG (Brazil)
2011-07-01
Full text: We consider an imaginary time functional integral formulation of a two-flavor, 3 + 1 lattice QCD model with Wilson's action and in the strong coupling regime (with a small hopping parameter, {kappa}0, and a much smaller plaquette coupling, {beta} = 1/g{sub 0}{sup 2}, so that the quarks and glueballs are heavy). The model has local SU(3){sub c} gauge and global SU(2){sub f} flavor symmetries, and incorporates the corresponding part of the eightfold way particles: baryons (mesons) of asymptotic mass -3ln{kappa}(-2 ln {kappa}). We search for pentaquark states as meson-baryon bound states in the energy-momentum spectrum of the model, using a lattice Bethe-Salpeter equation. This equation is solved within a ladder approximation, given by the lowest nonvanishing order in {kappa} and {beta} of the Bethe-Salpeter kernel. It includes order 2 contributions with a q-barq exchange potential together with a contribution that is a local-in-space, energy-dependent potential. The attractive or repulsive nature of the exchange interaction depends on the spin of the meson-baryon states. The Bethe-Salpeter equation presents integrable singularities, forcing the couplings to be above a threshold value for the meson and the baryon to bind in a pentaquark. We analyzed all the total isospin sectors, I = 1/2/3/2/ 5/2, for the system. For all I, the net attraction resulting from the two sources of interaction is not strong enough for the meson and the baryon to bind. Thus, within our approximation, these pentaquark states are not present up to near the free meson-baryon energy threshold of - 5 ln{kappa}. This result is to be contrasted with the spinless case for which our method detects meson-baryon bound states, as well as for Yukawa effective baryon and meson field models. A physical interpretation of our results emerges from an approximate correspondence between meson-baryon bound states and negative energy states of a one-particle lattice Schroedinger Hamiltonian
Ilgen, Julian; Kaltschnee, Lukas; Thiele, Christina M.
2018-01-01
Motivated by the persisting need for enhanced resolution in solution state NMR spectra, pure shift techniques such as Zangger-Sterk decoupling have recently attracted widespread interest. These techniques for homonuclear decoupling offer enhanced resolution in one- and multidimensional proton detected experiments by simplifying multiplet structures. In this work, a modification to the popular Zangger-Sterk technique PEPSIE (Perfect Echo Pure Shift Improved Experiment) is presented, which decouples pairs of spins even if they share the same volume element. This in turn can drastically improve the sensitivity, as compared to classical Zangger-Sterk decoupling, as larger volume elements can be used to collect the detected signal. Most interestingly, even in the presence of moderate strong coupling, the PEPSIE experiment produces clean and widely artifact free spectra. In order to better understand this - to us initially - surprising behaviour we performed analyses using numerical simulations and derived an (approximate) analytical solution from density matrix formalism. We show that this experiment is particularly suitable to study samples with strong signal clustering, a situation which can render classic Zangger-Sterk decoupling inefficient.
Energy Technology Data Exchange (ETDEWEB)
Acosta, L.; Martel, I.; Perez-Bernal, F.; Rodriguez, D.; Sanchez-Benitez, A.M. [Universidad de Huelva, Departamento de Fisica Aplicada, Huelva (Spain); Alvarez, M.A.G.; Gomez-Camacho, J. [Universidad de Sevilla, Departamento de Fisica Atomica Molecular y Nuclear, Sevilla (Spain); Universidad de Sevilla-CSIC-Junta de Andalucia, Centro Nacional de Aceleradores, Sevilla (Spain); Andres, M.V.; Espino, J.M.; Moro, A.M.; Mukha, I. [Universidad de Sevilla, Departamento de Fisica Atomica Molecular y Nuclear, Sevilla (Spain); Borge, M.J.G.; Cortes, M.; Galaviz, D.; Maira, A.; Reillo, E.; Tengblad, O. [CSIC, Madrid, Instituto de Estructura de la Materia, Madrid (Spain); Rusek, K. [The Andrzej Soltan Institute for Nuclear Studies, Warsaw (Poland)
2009-12-15
The angular distribution for {sup 11}Be+{sup 120}Sn quasielastic scattering at E{sub lab}=32 MeV was measured at REX-ISOLDE, CERN. The interpretation of the data in terms of coupled-channel calculations suggests a strong coupling with the p-states lying in the continuum. (orig.)
The strongly coupled fourth family and a first-order electroweak phase transition. 1. Quark sector
International Nuclear Information System (INIS)
Kikukawa, Yoshio; Kohda, Masaya; Yasuda, Junichiro
2009-01-01
In models of dynamical electroweak symmetry breaking due to strongly coupled fourth-family quarks and leptons, their low-energy effective descriptions may involve multiple composite Higgs fields, leading to a possibility that the electroweak phase transition at finite temperature is first-order due to the Coleman-Weinberg mechanism. We examine the behavior of the electroweak phase transition on the basis of the effective renormalizable Yukawa theory, which consists of the fourth-family quarks and two SU(2)-doublet Higgs fields corresponding to the bilinear operators of the fourth-family quarks with/without imposing the compositeness condition. The strength of the first-order phase transition is estimated using the finite-temperature effective potential at one loop with ring improvement. In the Yukawa theory without the compositeness condition, it is found that there is a parameter region where the first-order phase transition is sufficiently strong for the electroweak baryogenesis with the experimentally acceptable Higgs boson and fourth-family quark masses. On the other hand, when the compositeness condition is imposed, the phase transition turns out to be weakly first-order, or possibly second-order, although the result is rather sensitive to the details of the compositeness condition. By combining with the result of the Yukawa theory without the compositeness condition, it is argued that with the fourth-family quark masses in the range of 330-480 GeV, corresponding to the compositeness scale in the range of 1.0-2.3 TeV, the four-fermion interaction among the fourth-family quarks does not lead to the strongly first-order electroweak phase transition. (author)
International Nuclear Information System (INIS)
Faucher, V.
2014-01-01
This HDR is dedicated to the research in the framework of fast transient dynamics for industrial fluid-structure systems carried in the Laboratory of Dynamic Studies from CEA, implementing new numerical methods for the modelling of complex systems and the parallel solution of large coupled problems on supercomputers. One key issue for the proposed approaches is the limitation to its minimum of the number of non-physical parameters, to cope with constraints arising from the area of usage of the concepts: safety for both nuclear applications (CEA, EDF) and aeronautics (ONERA), protection of the citizen (EC/JRC) in particular. Kinematic constraints strongly coupling structures (namely through unilateral contact) or fluid and structures (with both conformant or non-conformant meshes depending on the geometrical situation) are handled through exact methods including Lagrange Multipliers, with consequences on the solution strategy to be dealt with. This latter aspect makes EPX, the simulation code where the methods are integrated, a singular tool in the community of fast transient dynamics software. The document mainly relies on a description of the modelling needs for industrial fast transient scenarios, for nuclear applications in particular, and the proposed solutions built in the framework of the collaboration between CEA, EDF (via the LaMSID laboratory) and the LaMCoS laboratory from INSA Lyon. The main considered examples are the tearing of the fluid-filled tank after impact, the Code Disruptive Accident for a Generation IV reactor or the ruin of reinforced concrete structures under impact. Innovative models and parallel algorithms are thus proposed, allowing to carry out with robustness and performance the corresponding simulations on supercomputers made of interconnected multi-core nodes, with a strict preservation of the quality of the physical solution. This was particularly the main point of the ANR RePDyn project (2010-2013), with CEA as the pilot. (author
Inert two-Higgs-doublet model strongly coupled to a non-Abelian vector resonance
Rojas-Abatte, Felipe; Mora, Maria Luisa; Urbina, Jose; Zerwekh, Alfonso R.
2017-11-01
We study the possibility of a dark matter candidate having its origin in an extended Higgs sector which, at least partially, is related to a new strongly interacting sector. More concretely, we consider an i2HDM (i.e., a Type-I two Higgs doublet model supplemented with a Z2 under which the nonstandard scalar doublet is odd) based on the gauge group S U (2 )1×S U (2 )2×U (1 )Y . We assume that one of the scalar doublets and the standard fermion transform nontrivially under S U (2 )1 while the second doublet transforms under S U (2 )2. Our main hypothesis is that standard sector is weakly coupled while the gauge interactions associated to the second group is characterized by a large coupling constant. We explore the consequences of this construction for the phenomenology of the dark matter candidate and we show that the presence of the new vector resonance reduces the relic density saturation region, compared to the usual i2DHM, in the high dark matter mass range. In the collider side, we argue that the mono-Z production is the channel which offers the best chances to manifest the presence of the new vector field. We study the departures from the usual i2HDM predictions and show that the discovery of the heavy vector at the LHC is challenging even in the mono-Z channel since the typical cross sections are of the order of 10-2 fb .
Angular structure of jet quenching within a hybrid strong/weak coupling model
Energy Technology Data Exchange (ETDEWEB)
Casalderrey-Solana, Jorge [Rudolf Peierls Centre for Theoretical Physics, University of Oxford,1 Keble Road, Oxford OX1 3NP (United Kingdom); Departament de Física Quàntica i Astrofísica & Institut de Ciències del Cosmos (ICC),Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain); Gulhan, Doga Can [CERN, EP Department,CH-1211 Geneva 23 (Switzerland); Milhano, José Guilherme [CENTRA, Instituto Superior Técnico, Universidade de Lisboa,Av. Rovisco Pais, P-1049-001 Lisboa (Portugal); Laboratório de Instrumentação e Física Experimental de Partículas (LIP),Av. Elias Garcia 14-1, P-1000-149 Lisboa (Portugal); Theoretical Physics Department, CERN,Geneva (Switzerland); Pablos, Daniel [Departament de Física Quàntica i Astrofísica & Institut de Ciències del Cosmos (ICC),Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain); Rajagopal, Krishna [Center for Theoretical Physics, Massachusetts Institute of Technology,Cambridge, MA 02139 (United States)
2017-03-27
Within the context of a hybrid strong/weak coupling model of jet quenching, we study the modification of the angular distribution of the energy within jets in heavy ion collisions, as partons within jet showers lose energy and get kicked as they traverse the strongly coupled plasma produced in the collision. To describe the dynamics transverse to the jet axis, we add the effects of transverse momentum broadening into our hybrid construction, introducing a parameter K≡q̂/T{sup 3} that governs its magnitude. We show that, because of the quenching of the energy of partons within a jet, even when K≠0 the jets that survive with some specified energy in the final state are narrower than jets with that energy in proton-proton collisions. For this reason, many standard observables are rather insensitive to K. We propose a new differential jet shape ratio observable in which the effects of transverse momentum broadening are apparent. We also analyze the response of the medium to the passage of the jet through it, noting that the momentum lost by the jet appears as the momentum of a wake in the medium. After freezeout this wake becomes soft particles with a broad angular distribution but with net momentum in the jet direction, meaning that the wake contributes to what is reconstructed as a jet. This effect must therefore be included in any description of the angular structure of the soft component of a jet. We show that the particles coming from the response of the medium to the momentum and energy deposited in it leads to a correlation between the momentum of soft particles well separated from the jet in angle with the direction of the jet momentum, and find qualitative but not quantitative agreement with experimental data on observables designed to extract such a correlation. More generally, by confronting the results that we obtain upon introducing transverse momentum broadening and the response of the medium to the jet with available jet data, we highlight the
Wu, Ning; Feist, Johannes; Garcia-Vidal, Francisco J.
2016-11-01
We present a microscopic semianalytical theory for the description of organic molecules interacting strongly with a cavity mode. Exciton-vibration coupling within the molecule and exciton-cavity interaction are treated on an equal footing by employing a temperature-dependent variational approach. The interplay between strong exciton-vibration coupling and strong exciton-cavity coupling gives rise to a hybrid ground state, which we refer to as the lower polaron polariton. Explicit expressions for the ground-state wave function, the zero-temperature quasiparticle weight of the lower polaron polariton, the photoluminescence line strength, and the mean number of vibrational quanta are obtained in terms of the optimal variational parameters. The dependence of these quantities upon the exciton-cavity coupling strength reveals that strong cavity coupling leads to an enhanced vibrational dressing of the cavity mode, and at the same time a vibrational decoupling of the dark excitons, which in turn results in a lower polaron polariton resembling a single-mode dressed bare lower polariton in the strong-coupling regime. Thermal effects on several observables are briefly discussed.
Strongly coupled interaction between a ridge of fluid and an inviscid airflow
Paterson, C.
2015-07-01
© 2015 AIP Publishing LLC. The behaviour of a steady thin sessile or pendent ridge of fluid on an inclined planar substrate which is strongly coupled to the external pressure gradient arising from an inviscid airflow parallel to the substrate far from the ridge is described. When the substrate is nearly horizontal, a very wide ridge can be supported against gravity by capillary and/or external pressure forces; otherwise, only a narrower (but still wide) ridge can be supported. Classical thin-aerofoil theory is adapted to obtain the governing singular integro-differential equation for the profile of the ridge in each case. Attention is focused mainly on the case of a very wide sessile ridge. The effect of strengthening the airflow is to push a pinned ridge down near to its edges and to pull it up near to its middle. At a critical airflow strength, the upslope contact angle reaches the receding contact angle at which the upslope contact line de-pins, and continuing to increase the airflow strength beyond this critical value results in the de-pinned ridge becoming narrower, thicker, and closer to being symmetric in the limit of a strong airflow. The effect of tilting the substrate is to skew a pinned ridge in the downslope direction. Depending on the values of the advancing and receding contact angles, the ridge may first de-pin at either the upslope or the downslope contact line but, in general, eventually both contact lines de-pin. The special cases in which only one of the contact lines de-pins are also considered. It is also shown that the behaviour of a very wide pendent ridge is qualitatively similar to that of a very wide sessile ridge, while the important qualitative difference between the behaviour of a very wide ridge and a narrower ridge is that, in general, for the latter one or both of the contact lines may never de-pin.
Delord, T.; Nicolas, L.; Chassagneux, Y.; Hétet, G.
2017-12-01
A scheme for strong coupling between a single atomic spin and the rotational mode of levitating nanoparticles is proposed. The idea is based on spin readout of nitrogen-vacancy centers embedded in aspherical nanodiamonds levitating in an ion trap. We show that the asymmetry of the diamond induces a rotational confinement in the ion trap. Using a weak homogeneous magnetic field and a strong microwave driving we then demonstrate that the spin of the nitrogen-vacancy center can be strongly coupled to the rotational mode of the diamond.
On the evolution of jet energy and opening angle in strongly coupled plasma
International Nuclear Information System (INIS)
Chesler, Paul M.; Rajagopal, Krishna
2016-01-01
We calculate how the energy and the opening angle of jets in N=4 SYM theory evolve as they propagate through the strongly coupled plasma of that theory. We define the rate of energy loss dE jet /dx and the jet opening angle in a straightforward fashion directly in the gauge theory before calculating both holographically, in the dual gravitational description. In this way, we rederive the previously known result for dE jet /dx without the need to introduce a finite slab of plasma. We obtain a striking relationship between the initial opening angle of the jet, which is to say the opening angle that it would have had if it had found itself in vacuum instead of in plasma, and the thermalization distance of the jet. Via this relationship, we show that N=4 SYM jets with any initial energy that have the same initial opening angle and the same trajectory through the plasma experience the same fractional energy loss. We also provide an expansion that describes how the opening angle of the N=4 SYM jets increases slowly as they lose energy, over the fraction of their lifetime when their fractional energy loss is not yet large. We close by looking ahead toward potential qualitative lessons from our results for QCD jets produced in heavy collisions and propagating through quark-gluon plasma.
Precision determination of the strong coupling constant within a global PDF analysis arXiv
Ball, Richard D.; Del Debbio, Luigi; Forte, Stefano; Kassabov, Zahari; Rojo, Juan; Slade, Emma; Ubiali, Maria
We present a determination of the strong coupling constant $\\alpha_s(m_Z)$ based on the NNPDF3.1 determination of parton distributions, which for the first time includes constraints from jet production, top-quark pair differential distributions, and the $Z$ $p_T$ distributions using exact NNLO theory. Our result is based on a novel extension of the NNPDF methodology - the correlated replica method - which allows for a simultaneous determination of $\\alpha_s$ and the PDFs with all correlations between them fully taken into account. We study in detail all relevant sources of experimental, methodological and theoretical uncertainty. At NNLO we find $\\alpha_s(m_Z) = 0.1185 \\pm 0.0005^\\text{(exp)}\\pm 0.0001^\\text{(meth)}$, showing that methodological uncertainties are negligible. We conservatively estimate the theoretical uncertainty due to missing higher order QCD corrections (N$^3$LO and beyond) from half the shift between the NLO and NNLO $\\alpha_s$ values, finding $\\Delta\\alpha^{\\rm th}_s =0.0011$.
Confined surface plasmon sensors based on strongly coupled disk-in-volcano arrays.
Ai, Bin; Wang, Limin; Möhwald, Helmuth; Yu, Ye; Zhang, Gang
2015-02-14
Disk-in-volcano arrays are reported to greatly enhance the sensing performance due to strong coupling in the nanogaps between the nanovolcanos and nanodisks. The designed structure, which is composed of a nanovolcano array film and a disk in each cavity, is fabricated by a simple and efficient colloidal lithography method. By tuning structural parameters, the disk-in-volcano arrays show greatly enhanced resonances in the nanogaps formed by the disks and the inner wall of the volcanos. Therefore they respond to the surrounding environment with a sensitivity as high as 977 nm per RIU and with excellent linear dependence on the refraction index. Moreover, through mastering the fabrication process, biological sensing can be easily confined to the cavities of the nanovolcanos. The local responsivity has the advantages of maximum surface plasmon energy density in the nanogaps, reducing the sensing background and saving expensive reagents. The disk-in-volcano arrays also possess great potential in applications of optical and electrical trapping and single-molecule analysis, because they enable establishment of electric fields across the gaps.
Measurement of jet production with the ATLAS detector and extraction of the strong coupling constant
Sawyer, Lee; The ATLAS collaboration
2017-01-01
The production of jets at hadron colliders provides a stringent test of perturbative QCD at the highest energies. The process can also be used to probe the gluon density function of the proton. Specific topologies can be used to extract the strong coupling constant. The ATLAS collaboration has recently measured the inclusive jet production cross section in data collected at a center-of-mass energy of 8TeV and 13TeV. The measurements have been performed differentially in jet rapidity and transverse momentum. The collaboration also presents a first measurement of the di-jet cross section at a center-of-mass energy of 13TeV as a function of the di-jet mass and rapidity. The results have been compared with state-of-the-art theory predictions at NLO in pQCD, interfaced with different parton distribution functions and can be used to constrain the proton structure. We also present new measurements of transverse energy-energy correlations (TEEC) and their associated asymmetries (ATEEC) in multi-jet events at a center...
Mamo, Kiminad A.
2012-10-01
We study holographic RG flow of the shear viscosity tensor of anisotropic, strongly coupled {N}=4 super-Yang-Mills plasma by using its type IIB supergravity dual in anisotropic bulk spacetime. We find that the shear viscosity tensor has three independent components in the anisotropic bulk spacetime away from the boundary, and one of the components has a non-trivial RG flow while the other two have a trivial one. For the component of the shear viscosity tensor with non-trivial RG flow, we derive its RG flow equation, and solve the equation analytically to second order in the anisotropy parameter a. We derive the RG equation using the equation of motion, holographic Wilsonian RG method, and Kubo's formula. All methods give the same result. Solving the equation, we find that the ratio of the component of the shear viscosity tensor to entropy density η /s flows from above 1/{4π } the horizon (IR) to below 1/{4π } the boundary (UV) where it violates the holographic shear viscosity (Kovtun-Son-Starinets) bound and where it agrees with the other longitudinal component.
Wang, Hao; Cao, Yingjie; Sun, Cheng; Zou, Guifu; Huang, Jianwen; Kuai, Xiaoxiao; Zhao, Jianqing; Gao, Lijun
2017-09-22
High-performance and affordable electrocatalysts from earth-abundant elements are desirably pursued for water splitting involving hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Here, a bifunctional electrocatalyst of highly crystalline Mo 2 C nanoparticles supported on carbon sheets (Mo 2 C/CS) was designed toward overall water splitting. Owing to the highly active catalytic nature of Mo 2 C nanoparticles, the high surface area of carbon sheets and efficient charge transfer in the strongly coupled composite, the designed catalysts show excellent bifunctional behavior with an onset potential of -60 mV for HER and an overpotential of 320 mV to achieve a current density of 10 mA cm -2 for OER in 1 m KOH while maintaining robust stability. Moreover, the electrolysis cell using the catalyst only requires a low cell voltage of 1.73 V to achieve a current density of 10 mA cm -2 and maintains the activity for more than 100 h when employing the Mo 2 C/CS catalyst as both anode and cathode electrodes. Such high performance makes Mo 2 C/CS a promising electrocatalyst for practical hydrogen production from water splitting. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Engineering light emission of two-dimensional materials in both the weak and strong coupling regimes
Brotons-Gisbert, Mauro; Martínez-Pastor, Juan P.; Ballesteros, Guillem C.; Gerardot, Brian D.; Sánchez-Royo, Juan F.
2018-01-01
Two-dimensional (2D) materials have promising applications in optoelectronics, photonics, and quantum technologies. However, their intrinsically low light absorption limits their performance, and potential devices must be accurately engineered for optimal operation. Here, we apply a transfer matrix-based source-term method to optimize light absorption and emission in 2D materials and related devices in weak and strong coupling regimes. The implemented analytical model accurately accounts for experimental results reported for representative 2D materials such as graphene and MoS2. The model has been extended to propose structures to optimize light emission by exciton recombination in MoS2 single layers, light extraction from arbitrarily oriented dipole monolayers, and single-photon emission in 2D materials. Also, it has been successfully applied to retrieve exciton-cavity interaction parameters from MoS2 microcavity experiments. The present model appears as a powerful and versatile tool for the design of new optoelectronic devices based on 2D semiconductors such as quantum light sources and polariton lasers.
The ATLAS Measurements of Jet Production and the Strong Coupling Constant
Sawyer, Lee; The ATLAS collaboration
2017-01-01
The production of jets at hadron colliders provides a stringent test of perturbative QCD at the highest energies. The process can also be used to probe the gluon density in the parton distribution function of the proton. Specific topologies can be used to extract the strong coupling constant. The ATLAS collaboration has recently measured the inclusive jet production cross section in data collected at a center-of-mass energy of 8 TeV and 13 TeV. The measurements have been performed differentially in jet rapidity and transverse momentum. The collaboration also presents a first measurement of the dijet cross section at a center-of-mass energy of 13 TeV as a function of the dijet invariant mass and rapidity. The results have been compared with state-of-the-art theory predictions at NLO in pQCD, interfaced with different parton distribution functions and can be used to constrain the proton structure. We also present new measurements of transverse energy-energy correlations (TEEC) and their associated asymmetries (...
Heavy flavor at the large hadron collider in a strong coupling approach
Energy Technology Data Exchange (ETDEWEB)
He, Min [Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094 (China); Fries, Rainer J.; Rapp, Ralf [Cyclotron Institute and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843-3366 (United States)
2014-07-30
Employing nonperturbative transport coefficients for heavy-flavor (HF) diffusion through quark–gluon plasma (QGP), hadronization and hadronic matter, we compute D- and B-meson observables in Pb+Pb (√(s)=2.76 TeV) collisions at the LHC. Elastic heavy-quark scattering in the QGP is evaluated within a thermodynamic T-matrix approach, generating resonances close to the critical temperature which are utilized for recombination into D and B mesons, followed by hadronic diffusion using effective hadronic scattering amplitudes. The transport coefficients are implemented via Fokker–Planck Langevin dynamics within hydrodynamic simulations of the bulk medium in nuclear collisions. The hydro expansion is quantitatively constrained by transverse-momentum spectra and elliptic flow of light hadrons. Our approach thus incorporates the paradigm of a strongly coupled medium in both bulk and HF dynamics throughout the thermal evolution of the system. At low and intermediate p{sub T}, HF observables at LHC are reasonably well accounted for, while discrepancies at high p{sub T} are indicative for radiative mechanisms not included in our approach.
International Nuclear Information System (INIS)
Decker, K.; Hamburg Univ.
1985-12-01
An efficient description of all clusters contributing to the strong coupling expansion of the mass gap in three-dimensional pure Z 2 lattice gauge theory is presented. This description is correct to all orders in the strong coupling expansion and is chosen in such a way that it remains valid in four dimensions for gauge group Z 2 . Relying on this description an algorithm has been constructed which generates and processes all the contributing graphs to the exact strong coupling expansion of the mass gap in the three-dimensional model in a fully automatic fashion. A major component of this algorithm can also be used to generate exact strong coupling expansions for the free energy logZ. The algorithm is correct to any order; thus the order of these expansions is only limited by the available computing power. The presentation of the algorithm is such that it can serve as a guide-line for the construction of a generalized one which would also generate exact strong coupling expansions for the masses of low-lying excited states of four-dimensional pure Yang-Mills theories. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Zhao, Haihua [Idaho National Laboratory; Zhang, Hongbin [Idaho National Laboratory; Zou, Ling [Idaho National Laboratory; Martineau, Richard Charles [Idaho National Laboratory
2015-03-01
The reactor core isolation cooling (RCIC) system in a boiling water reactor (BWR) provides makeup cooling water to the reactor pressure vessel (RPV) when the main steam lines are isolated and the normal supply of water to the reactor vessel is lost. The RCIC system operates independently of AC power, service air, or external cooling water systems. The only required external energy source is from the battery to maintain the logic circuits to control the opening and/or closure of valves in the RCIC systems in order to control the RPV water level by shutting down the RCIC pump to avoid overfilling the RPV and flooding the steam line to the RCIC turbine. It is generally considered in almost all the existing station black-out accidents (SBO) analyses that loss of the DC power would result in overfilling the steam line and allowing liquid water to flow into the RCIC turbine, where it is assumed that the turbine would then be disabled. This behavior, however, was not observed in the Fukushima Daiichi accidents, where the Unit 2 RCIC functioned without DC power for nearly three days. Therefore, more detailed mechanistic models for RCIC system components are needed to understand the extended SBO for BWRs. As part of the effort to develop the next generation reactor system safety analysis code RELAP-7, we have developed a strongly coupled RCIC system model, which consists of a turbine model, a pump model, a check valve model, a wet well model, and their coupling models. Unlike the traditional SBO simulations where mass flow rates are typically given in the input file through time dependent functions, the real mass flow rates through the turbine and the pump loops in our model are dynamically calculated according to conservation laws and turbine/pump operation curves. A simplified SBO demonstration RELAP-7 model with this RCIC model has been successfully developed. The demonstration model includes the major components for the primary system of a BWR, as well as the safety
Curious Consequences of Strong Coupling in NMR Experiments Involving Selective Pulses
Huth, Johannes; Fu, Riqiang; Bodenhausen, Geoffrey
This study is concerned with the effects of applying selective pulses to systems with strong second-order scalar couplings in isotropic phase, where different transitions ( rs) are associated with different transition matrix elements F+( rs) . Two unusual features can be distinguished: the nutation angle ("flip angle") depends on the matrix element of the irradiated transition ( rs), and, in contrast to the behavior of an isolated spin- {1}/{2} system, the norm of the three single-transition operators [ I( rs) x, I( rs) y, I( rs) z] associated with the fictitious spin- {1}/{2} space of the irradiated transition ( rs) is generally not conserved. It is necessary to consider the single-transition operators [ I( rp) x, I( rp) y, I( rp) z] and [ I( sq) x, I( sq) y, I( sq) z] associated with all connected transitions ( rp) and ( sq) that share a common energy level ror swith the irradiated transition ( rs). If the pulse applied to the ( rs) transition is sufficiently selective, the transverse components I( rp) x, I( rp) y, I( sq) x, and I( sq) y, can be neglected, since their expectation values remain equal to zero after application of a selective pulse to the ( rs) transition, but the longitudinal components I( rp) zand I( sq) zacquire nonvanishing expectation values. When the selective pulse affects several transitions simultaneously, the response varies from one transition to another, depending on the matrix elements and the connectivities. These effects manifest themselves in unusual amplitudes and phases of signals excited by selective pulses, in particular in selective two-dimensional correlation spectra.
Electronic transport through a quantum dot chain with strong dot-lead coupling
International Nuclear Information System (INIS)
Liu, Yu; Zheng, Yisong; Gong, Weijiang; Gao, Wenzhu; Lue, Tianquan
2007-01-01
By means of the non-equilibrium Green function technique, the electronic transport through an N-quantum-dot chain is theoretically studied. By calculating the linear conductance spectrum and the local density of states in quantum dots, we find the resonant peaks in the spectra coincides with the eigen-energies of the N-quantum-dot chain when the dot-lead coupling is relatively weak. With the increase of the dot-lead coupling, such a correspondence becomes inaccurate. When the dot-lead coupling exceeds twice the interdot coupling, such a mapping collapses completely. The linear conductance turn to reflect the eigen-energies of the (N-2)- or (N-1)-quantum dot chain instead. The two peripheral quantum dots do not manifest themselves in the linear conductance spectrum. More interestingly, with the further increase of the dot-lead coupling, the system behaves just like an (N-2)- or (N-1)-quantum dot chain in weak dot-lead coupling limit, since the resonant peaks becomes narrower with the increase of dot-lead coupling
Neon diffusion kinetics and implications for cosmogenic neon paleothermometry in feldspars
Tremblay, Marissa M.; Shuster, David L.; Balco, Greg; Cassata, William S.
2017-05-01
Observations of cosmogenic neon concentrations in feldspars can potentially be used to constrain the surface exposure duration or surface temperature history of geologic samples. The applicability of cosmogenic neon to either application depends on the temperature-dependent diffusivity of neon isotopes. In this work, we investigate the kinetics of neon diffusion in feldspars of different compositions and geologic origins through stepwise degassing experiments on single, proton-irradiated crystals. To understand the potential causes of complex diffusion behavior that is sometimes manifest as nonlinearity in Arrhenius plots, we compare our results to argon stepwise degassing experiments previously conducted on the same feldspars. Many of the feldspars we studied exhibit linear Arrhenius behavior for neon whereas argon degassing from the same feldspars did not. This suggests that nonlinear behavior in argon experiments is an artifact of structural changes during laboratory heating. However, other feldspars that we examined exhibit nonlinear Arrhenius behavior for neon diffusion at temperatures far below any known structural changes, which suggests that some preexisting material property is responsible for the complex behavior. In general, neon diffusion kinetics vary widely across the different feldspars studied, with estimated activation energies (Ea) ranging from 83.3 to 110.7 kJ/mol and apparent pre-exponential factors (D0) spanning three orders of magnitude from 2.4 × 10-3 to 8.9 × 10-1 cm2 s-1. As a consequence of this variability, the ability to reconstruct temperatures or exposure durations from cosmogenic neon abundances will depend on both the specific feldspar and the surface temperature conditions at the geologic site of interest.
Determinations of the QCD strong coupling αsub(s) and the scale Λsub(QCD)
International Nuclear Information System (INIS)
Duke, D.W.; Roberts, R.G.
1984-08-01
The authors review determinations, via experiment of the strong coupling of QCD, αsub(s). In almost every case, the results are used of perturbative QCD to make the necessary extraction from data. These include scaling violations of deep inelastic scattering, e + e - annihilation experiments (including quarkonium decays) and lepton pair production. Finally estimates for Λ from lattice calculations are listed. (author)
DEFF Research Database (Denmark)
Van Vlack, C.; Kristensen, Philip Trøst; Hughes, S.
2012-01-01
the dot to the detector, we demonstrate that the strong-coupling regime should be observable in the far-field spontaneous emission spectrum, even at room temperature. The vacuum-induced emission spectra show that the usual vacuum Rabi doublet becomes a rich spectral triplet or quartet with two of the four...
Energy Technology Data Exchange (ETDEWEB)
Casalderrey-Solana, Jorge [Departament d' Estructura i Constituents de la Matèria and Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain); Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Gulhan, Doga Can [Laboratory for Nuclear Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Milhano, José Guilherme [CENTRA, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, P-1049-001 Lisboa (Portugal); Physics Department, Theory Unit, CERN, CH-1211 Genève 23 (Switzerland); Pablos, Daniel [Departament d' Estructura i Constituents de la Matèria and Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain); Rajagopal, Krishna [Laboratory for Nuclear Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)
2016-12-15
Within a hybrid strong/weak coupling model for jets in strongly coupled plasma, we explore jet modifications in ultra-relativistic heavy ion collisions. Our approach merges the perturbative dynamics of hard jet evolution with the strongly coupled dynamics which dominates the soft exchanges between the fast partons in the jet shower and the strongly coupled plasma itself. We implement this approach in a Monte Carlo, which supplements the DGLAP shower with the energy loss dynamics as dictated by holographic computations, up to a single free parameter that we fit to data. We then augment the model by incorporating the transverse momentum picked up by each parton in the shower as it propagates through the medium, at the expense of adding a second free parameter. We use this model to discuss the influence of the transverse broadening of the partons in a jet on intra-jet observables. In addition, we explore the sensitivity of such observables to the back-reaction of the plasma to the passage of the jet.
Silicon compounds of neon and argon
Czech Academy of Sciences Publication Activity Database
Roithová, J.; Schröder, Detlef
-, č. 46 (2009), s. 8788-8790 ISSN 1433-7851 R&D Projects: GA ČR GA203/09/1223 Grant - others:ERC(XE) Adg HORIZOMS Institutional research plan: CEZ:AV0Z40550506 Keywords : argon * bond formation * dications * neon Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 11.829, year: 2009
Chen, Gengyan; Liu, Jing-Feng; Jiang, Haoxiang; Zhuo, Xiao-Lu; Yu, Yi-Cong; Jin, Chongjun; Wang, Xue-Hua
2013-04-23
The quality factor and mode volume of a nanocavity play pivotal roles in realizing the strong coupling interaction between the nanocavity mode and a quantum dot. We present an extremely simple method to obtain the mode volume and investigate the effect of the slab thickness on the quality factor and mode volume of photonic crystal slab nanocavities. We reveal that the mode volume is approximatively proportional to the slab thickness. As compared with the previous structure finely optimized by introducing displacement of the air holes, via tuning the slab thickness, the quality factor can be enhanced by about 22%, and the ratio between the coupling coefficient and the nanocavity decay rate can be enhanced by about 13%. This can remarkably enhance the capability of the photonic crystal slab nanocavity for realizing the strong coupling interaction. The slab thickness tuning approach is feasible and significant for the experimental fabrication of the solid-state nanocavities.
Energy Technology Data Exchange (ETDEWEB)
Golden, Kenneth I.
2002-09-16
The main research accomplishments/findings of the project were the following: (1) Publication of an in-depth review article in Physics of Plasmas on the quasilocalized charge approximation (QLCA) in strongly coupled plasma physics and its application to a variety of Coulomb systems: the model one-component plasma in three and two dimensions, binary ionic mixtures, charged particle bilayers, and laboratory dusty plasmas. (2) In the strongly coupled Coulomb liquid phase, the physical basis of the QLCA, namely, the caging of particles trapped in slowly fluctuating local potential minima, is supported by molecular dynamics simulation of the classical three-dimensional one-component plasma. (3) The QLCA theory, when applied to the analysis of the collective modes in strongly coupled charged particle bilayers, predicts the existence of a remarkable long-wavelength energy gap in the out-of-phase excitation spectrum. More recent theoretical calculations based on the three principal frequency-moment sum rules reveal that the gap persists for arbitrary coupling strengths and over the entire classical to quantum domain all the way down to zero temperature. The existence of the energy gap has now been confirmed in a molecular dynamics simulation of the charged particle bilayer. (4) New compressibility and third-frequency-moment sum rules for multilayer plasmas were formulated and applied to the analysis of the dynamical structure function of charged particle bilayers and superlattices. (5) An equivalent of the Debye-Huckel weak coupling equilibrium theory for classical charged particle bilayer and superlattice plasmas was formulated. (6) The quadratic fluctuation-dissipation theorem (QFDT) for layered classical plasmas was formulated. (7) The QFDT was applied to a powerful kinetic theory-based description of the density-density response function and long-wavelength plasma mode behavior in strongly coupled two-dimensional Coulomb fluids in the weakly degenerate quantum domain.
Two-qubit gate operations in superconducting circuits with strong coupling and weak anharmonicity
International Nuclear Information System (INIS)
Lü Xinyou; Ashhab, S; Cui Wei; Wu Rebing; Nori, Franco
2012-01-01
We theoretically study the implementation of two-qubit gates in a system of two coupled superconducting qubits. In particular, we analyze two-qubit gate operations under the condition that the coupling strength is comparable with or even larger than the anharmonicity of the qubits. By numerically solving the time-dependent Schrödinger equation under the assumption of negligible decoherence, we obtain the dependence of the two-qubit gate fidelity on the system parameters in the case of both direct and indirect qubit-qubit coupling. Our numerical results can be used to identify the ‘safe’ parameter regime for experimentally implementing two-qubit gates with high fidelity in these systems. (paper)
Strong climate coupling of terrestrial and marine environments in the Miocene of northwest Europe
Donders, T.H.; Weijers, J.W.H.; Munsterman, D.K.; Kloosterboer-van Hoeve, M.L.; Buckles, L.K.; Pancost, R.D.; Schouten, S.; Sinninghe Damsté, J.S.; Brinkhuis, H.
2009-01-01
A palynological and organic geochemical record from a shallow marine paleoenvironmental setting in SE Netherlands documents the coupled marine and terrestrial climate evolution from the late Burdigalian (∼ 17 Ma) through the early Zanclean (∼ 4.5 Ma). Proxy climate records show several coeval
Electrical control of spontaneous emission and strong coupling for a single quantum dot
DEFF Research Database (Denmark)
Laucht, A.; Hofbauer, F.; Hauke, N.
2009-01-01
coupling regime, and electrical control of zerodimensional polaritons is demonstrated for the highest-Q cavities (Q > 12 000). Vacuum Rabi splittings up to 120μeV are observed, larger than the linewidths of either the decoupled exciton ( 6 40μeV) or cavity mode. These observations represent a voltage...
Zhang, Yu-Yu; Chen, Xiang-You
2017-12-01
An unexplored nonperturbative deep strong coupling (npDSC) achieved in superconducting circuits has been studied in the anisotropic Rabi model by the generalized squeezing rotating-wave approximation. Energy levels are evaluated analytically from the reformulated Hamiltonian and agree well with numerical ones in a wide range of coupling strength. Such improvement ascribes to deformation effects in the displaced-squeezed state presented by the squeezed momentum variance, which are omitted in previous displaced states. The atom population dynamics confirms the validity of our approach for the npDSC strength. Our approach offers the possibility to explore interesting phenomena analytically in the npDSC regime in qubit-oscillator experiments.
Resonant photopumping of a neon lasant plasma by a sodium pump plasma
International Nuclear Information System (INIS)
Young, F.C.; Apruzese, J.P.; Burkhalter, P.G.; Cooperstein, G.; Davis, J.; Mosher, D.; Ottinger, P.F.; Scherrer, V.E.; Stephanakis, S.J.; Mehlman, C.; Welch, B.L.
1988-01-01
Resonant photopumping of heliumlike neon by helium like sodium is being investigated to extend this pumping technique to the soft x-ray region. In the Na-pump/Ne-lasant system, the 1s 2 -1s2p 1 P 1 line of Na X at 11.0027 A differs by 2 parts in 10 4 from the 1s 2 -1s 4 p 1 P 1 line of Ne 1X at 11.0003 A. This wavelength difference corresponds to about one Doppler width at the sodium plasma temperatures (200-500 eV) required for strong Na X pump radiation. Sodium line radiation of sufficient power irradiating a properly prepared neon plasma will cause overpopulation of the Ne 1X n = 4 singlet level leading to lasing in the 4-3, 4-2, and possibly 3-2 singlet transitions. Experimentally, the current pulse from the NRL Gamble-II generator is used to produce side-by-side z-pinch plasmas of sodium fluoride (NaF) and neon. The discharges are viewed radially with x-ray diagnostics including time-integrated pinhole cameras, time-resolved x-ray diodes, and a time-integrated curved-crystal spectrograph. Measurements of the neon plasma indicate that a discharge current of about 200 kA is required to produce a neon lasant with a dominant heliumlike ground-state population. For fluorescence experiments, appropriate neon lasant conditions (density of about 10 18 cm -3 and temperature of 50-100 eV) must be produced at the time of the intense sodium pump-line radiation. Fluorescence is demonstrated by observing enhancement of the 4-1 line (He-γ) from the neon plasma relative to the 3-1 line (He-γ) when the neon is pumped by sodium. An increase in this γ-to-β ratio of 25% has been observed when the sodium pump radiation is present. The results of recent experiments are reported, and their implications for future experiments are discussed
Strong Linear Dichroism in Spin-Polarized Photoemission from Spin-Orbit-Coupled Surface States.
Bentmann, H; Maaß, H; Krasovskii, E E; Peixoto, T R F; Seibel, C; Leandersson, M; Balasubramanian, T; Reinert, F
2017-09-08
A comprehensive understanding of spin-polarized photoemission is crucial for accessing the electronic structure of spin-orbit coupled materials. Yet, the impact of the final state in the photoemission process on the photoelectron spin has been difficult to assess in these systems. We present experiments for the spin-orbit split states in a Bi-Ag surface alloy showing that the alteration of the final state with energy may cause a complete reversal of the photoelectron spin polarization. We explain the effect on the basis of ab initio one-step photoemission theory and describe how it originates from linear dichroism in the angular distribution of photoelectrons. Our analysis shows that the modulated photoelectron spin polarization reflects the intrinsic spin density of the surface state being sampled differently depending on the final state, and it indicates linear dichroism as a natural probe of spin-orbit coupling at surfaces.
The strong running coupling from an approximate gluon Dyson-Schwinger equation
International Nuclear Information System (INIS)
Alkofer, R.; Hauck, A.
1996-01-01
Using Mandelstam's approximation to the gluon Dyson-Schwinger equation we calculate the gluon self-energy in a renormalisation group invariant fashion. We obtain a non-perturbative Β function. The scaling behavior near the ultraviolet stable fixed point is in good agreement with perturbative QCD. No further fixed point for positive values of the coupling is found: α S increases without bound in the infrared
Energy Technology Data Exchange (ETDEWEB)
Kononov, A.; Egorov, S. V. [Russian Academy Sciences, Institute of Solid State Physics (Russian Federation); Kvon, Z. D.; Mikhailov, N. N.; Dvoretsky, S. A. [Institute of Semiconductor Physics (Russian Federation); Deviatov, E. V., E-mail: dev@issp.ac.ru [Russian Academy Sciences, Institute of Solid State Physics (Russian Federation)
2016-11-15
We experimentally investigate spin-polarized electron transport between a permalloy ferromagnet and the edge of a two-dimensional electron system with band inversion, realized in a narrow, 8 nm wide, HgTe quantum well. In zero magnetic field, we observe strong asymmetry of the edge potential distribution with respect to the ferromagnetic ground lead. This result indicates that the helical edge channel, specific for the structures with band inversion even at the conductive bulk, is strongly coupled to the ferromagnetic side contact, possibly due to the effects of proximity magnetization. This allows selective and spin-sensitive contacting of helical edge states.
Wallraff, A; Schuster, D I; Blais, A; Gambetta, J M; Schreier, J; Frunzio, L; Devoret, M H; Girvin, S M; Schoelkopf, R J
2007-08-03
Sideband transitions are spectroscopically probed in a system consisting of a Cooper pair box strongly but nonresonantly coupled to a superconducting transmission line resonator. When the Cooper pair box is operated at the optimal charge bias point, the symmetry of the Hamiltonian requires a two-photon process to access sidebands. The observed large dispersive ac-Stark shifts in the sideband transitions induced by the strong nonresonant drives agree well with our theoretical predictions. Sideband transitions are important in realizing qubit-photon and qubit-qubit entanglement in the circuit quantum electrodynamics architecture for quantum information processing.
Negative tunneling magneto-resistance in quantum wires with strong spin-orbit coupling.
Han, Seungju; Serra, Llorenç; Choi, Mahn-Soo
2015-07-01
We consider a two-dimensional magnetic tunnel junction of the FM/I/QW(FM+SO)/I/N structure, where FM, I and QW(FM+SO) stand for a ferromagnet, an insulator and a quantum wire with both magnetic ordering and Rashba spin-orbit (SOC), respectively. The tunneling magneto-resistance (TMR) exhibits strong anisotropy and switches sign as the polarization direction varies relative to the quantum-wire axis, due to interplay among the one-dimensionality, the magnetic ordering, and the strong SOC of the quantum wire.
International Nuclear Information System (INIS)
Vallurupalli, Pramodh; Scott, Lincoln; Williamson, James R.; Kay, Lewis E.
2007-01-01
Simulation and experiment have been used to establish that significant artifacts can be generated in X-pulse CPMG relaxation dispersion experiments recorded on heteronuclear ABX spin-systems, such as 13 C i - 13 C j - 1 H, where 13 C i and 13 C j are strongly coupled. A qualitative explanation of the origin of these artifacts is presented along with a simple method to significantly reduce them. An application to the measurement of 1 H CPMG relaxation dispersion profiles in an HIV-2 TAR RNA molecule where all ribose sugars are protonated at the 2' position, deuterated at all other sugar positions and 13 C labeled at all sugar carbons is presented to illustrate the problems that strong 13 C- 13 C coupling introduces and a simple solution is proposed
Energy Technology Data Exchange (ETDEWEB)
Malaescu, B. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Starovoitov, P. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2012-03-15
We perform a determination of the strong coupling constant using the latest ATLAS inclusive jet cross section data, from proton-proton collisions at {radical}(s)=7 TeV, and their full information on the bin-to-bin correlations. Several procedures for combining the statistical information from the different data inputs are studied and compared. The theoretical prediction is obtained using NLO QCD, and it also includes non-perturbative corrections. Our determination uses inputs with transverse momenta between 45 and 600 GeV, the running of the strong coupling being also tested in this range. Good agreement is observed when comparing our result with the world average at the Z-boson scale, as well as with the most recent results from the Tevatron. (orig.)
Casalderrey-Solana, Jorge; Milhano, Jose Guilherme; Pablos, Daniel; Rajagopal, Krishna
2016-06-11
We confront a hybrid strong/weak coupling model for jet quenching to data from LHC heavy ion collisions. The model combines the perturbative QCD physics at high momentum transfer and the strongly coupled dynamics of non- abelian gauge theories plasmas in a phenomenological way. By performing a full Monte Carlo simulation, and after fitting one single parameter, we successfully describe several jet observables at the LHC, including dijet and photon jet measurements. Within current theoretical and experimental uncertainties, we find that such observables show little sensitivity to the specifics of the microscopic energy loss mechanism. We also present a new observable, the ratio of the fragmentation function of inclusive jets to that of the associated jets in dijet pairs, which can discriminate among different medium models. Finally, we discuss the importance of plasma response to jet passage in jet shapes.
Effect of the strong coupling on the exchange bias field in IrMn/Py/Ru/Co spin valves
Tarazona, H. S.; Alayo, W.; Landauro, C. V.; Quispe-Marcatoma, J.
2018-01-01
The IrMn/Py/Ru/Co (Py = Ni81Fe19) spin valves have been produced by sputtering deposition and analyzed by magnetization measurements and a theoretical modelling of their exchange interactions, based on the macro-spin model. The Ru thickness was grown between 6 and 22 Å, which is small enough to promote strong indirect coupling between Py and Co. Results of measurements showed a large and gradual change in the shape of hysteresis loops when the Ru thickness was varied. The theoretical analysis, using numerical calculations based on the gradient conjugate method, provides the exchange coupling constants (bilinear and biquadratic), the exchange anisotropy fields and the magnetic anisotropy fields (uniaxial and rotatable). The exchange bias fields of spin valves were compared to that of a IrMn/Py bilayer. We found that the difference between these fields oscillates with Ru thickness in the same manner as the bilinear coupling constants.
Vafek, Oskar; Chubukov, Andrey V.
2017-02-01
We present a novel mechanism of s -wave pairing in Fe-based superconductors. The mechanism involves holes near dx z/dy z pockets only and is applicable primarily to strongly hole doped materials. We argue that as long as the renormalized Hund's coupling J exceeds the renormalized interorbital Hubbard repulsion U', any finite spin-orbit coupling gives rise to s -wave superconductivity. This holds even at weak coupling and regardless of the strength of the intraorbital Hubbard repulsion U . The transition temperature grows as the hole density decreases. The pairing gaps are fourfold symmetric, but anisotropic, with the possibility of eight accidental nodes along the larger pocket. The resulting state is consistent with the experiments on KFe2 As2 .
Emission of strong Terahertz pulses from laser wakefields in weakly coupled plasma
Energy Technology Data Exchange (ETDEWEB)
Singh, Divya, E-mail: dsingh@rajdhani.du.ac.in [PWAPA Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110 016 (India); Department of Physics & Electronics, Rajdhani College, University of Delhi, Raja Garden, Ring Road, New Delhi 110015 (India); Malik, Hitendra K. [PWAPA Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110 016 (India)
2016-09-01
The present paper discusses the laser plasma interaction for the wakefield excitation and the role of external magnetic field for the emission of Terahertz radiation in a collisional plasma. Flat top lasers are shown to be more appropriate than the conventional Gaussian lasers for the effective excitation of wakefields and hence, the generation of strong Terahertz radiation through the transverse component of wakefield.
Sokhoyan, R.; Azizbekyan, H.; Leroy, C.; Ishkhanyan, A.
2011-04-01
We discuss the strong-coupling regime of the nonlinear Landau-Zener problem occurring at coherent photo- and magneto-association of ultracold atoms. We apply a variational approach to an exact third-order nonlinear differential equation for the molecular state probability and construct an accurate approximation describing the time dynamics of the coupled atom-molecule system. The resultant solution improves the accuracy of the previous approximation [22]. The obtained results reveal a remarkable observation that in the strong-coupling limit, the resonance crossing is mostly governed by the nonlinearity, while the coherent atom-molecule oscillations occurring soon after crossing the resonance are principally of a linear nature. This observation is supposedly general for all nonlinear quantum systems having the same generic quadratic nonlinearity, due to the basic attributes of the resonance crossing processes in such systems. The constructed approximation turns out to have a larger applicability range than it was initially expected, covering the whole moderate-coupling regime for which the proposed solution accurately describes ail the main characteristics of the system evolution except the amplitude of the coherent atom-molecule oscillation, which is rather overestimated.
Yang, Bowen; Lohmann, Mark; Barroso, David; Liao, Ingrid; Lin, Zhisheng; Liu, Yawen; Bartels, Ludwig; Watanabe, Kenji; Taniguchi, Takashi; Shi, Jing
2017-07-01
Despite its extremely weak intrinsic spin-orbit coupling (SOC), graphene has been shown to acquire considerable SOC by proximity coupling with exfoliated transition metal dichalcogenides (TMDs). Here we demonstrate strong induced Rashba SOC in graphene that is proximity coupled to a monolayer TMD film, Mo S2 or WS e2 , grown by chemical-vapor deposition with drastically different Fermi level positions. Graphene/TMD heterostructures are fabricated with a pickup-transfer technique utilizing hexagonal boron nitride, which serves as a flat template to promote intimate contact and therefore a strong interfacial interaction between TMD and graphene as evidenced by quenching of the TMD photoluminescence. We observe strong induced graphene SOC that manifests itself in a pronounced weak-antilocalization (WAL) effect in the graphene magnetoconductance. The spin-relaxation rate extracted from the WAL analysis varies linearly with the momentum scattering time and is independent of the carrier type. This indicates a dominantly Dyakonov-Perel spin-relaxation mechanism caused by the induced Rashba SOC. Our analysis yields a Rashba SOC energy of ˜1.5 meV in graphene/WS e2 and ˜0.9 meV in graphene/Mo S2 . The nearly electron-hole symmetric nature of the induced Rashba SOC provides a clue to possible underlying SOC mechanisms.
A bridge between weak and strong coupling regions: BRS symmetries as a guiding principle
International Nuclear Information System (INIS)
Shintani, M.
1987-04-01
By imposing extended BRS symmetries on the Yang-Mills Lagrangian, we obtained two types of BRS invariant Lagrangians, i.e. Lagrangians of the non-gauge type and the gauge type. A Lagrangian of the non-gauge type, which was previously obtained by us, can yield the linearly rising potential between a quark and anti-quark pair at the one-loop level. By smoothly relating the running coupling constant in the confining region to that in the asymptotically free region, we deduce a relationship between the string tensions and Λ QCD , which shows good agreement with experiments. (author). 20 refs, 1 fig
Thermal spectral functions of strongly coupled N = 4 supersymmetric Yang-Mills theory.
Kovtun, Pavel; Starinets, Andrei
2006-04-07
We use the gauge-gravity duality conjecture to compute spectral functions of the stress-energy tensor in finite-temperature N = 4 supersymmetric Yang-Mills theory in the limit of large N(c) and large 't Hooft coupling. The spectral functions exhibit peaks characteristic of hydrodynamic modes at small frequency, and oscillations at intermediate frequency. The nonperturbative spectral functions differ qualitatively from those obtained in perturbation theory. The results may prove useful for lattice studies of transport processes in thermal gauge theories.
Non-perturbative computation of the strong coupling constant on the lattice
International Nuclear Information System (INIS)
Sommer, Rainer; Humboldt-Universitaet, Berlin; Wolff, Ulli
2015-01-01
We review the long term project of the ALPHA collaboration to compute in QCD the running coupling constant and quark masses at high energy scales in terms of low energy hadronic quantities. The adapted techniques required to numerically carry out the required multiscale non-perturbative calculation with our special emphasis on the control of systematic errors are summarized. The complete results in the two dynamical flavor approximation are reviewed and an outlook is given on the ongoing three flavor extension of the programme with improved target precision.
Plasmon mass and Drude weight in strongly spin-orbit-coupled 2D electron gases
Czech Academy of Sciences Publication Activity Database
Agarwal, A.; Chesi, S.; Jungwirth, Tomáš; Sinova, Jairo; Vignale, G.; Polini, M.
2011-01-01
Roč. 83, č. 11 (2011), 115135/1-115135/16 ISSN 1098-0121 R&D Projects: GA AV ČR KAN400100652; GA MŠk LC510 EU Projects: European Commission(XE) 215368 - SemiSpinNet Grant - others:AV ČR(CZ) AP0801 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : two-dimensional systems * spin-orbit coupling Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.691, year: 2011
Strong coupling between 0D and 2D modes in optical open microcavities
Trichet, A. A. P.; Dolan, P. R.; Smith, J. M.
2018-02-01
We present a study of the coupling between confined modes and continuum states in an open microcavity system. The confined states are the optical modes of a plano-concave Fabry–Pérot cavity while the continuum states are the propagating modes in a surrounding planar cavity. The length tunability of the open cavity system allows to study the evolution of localised modes as they are progressively deconfined and coupled to the propagating modes. We observe an anti-crossing between the confined and propagating modes proving that mode-mixing takes place in between these two families of modes, and identify 0D–2D mixed modes which exhibit reduced loss compared with their highly localised counterparts. For practical design, we investigate the details of the microcavity shape that can be used to engineer the degree of mode-mixing. This study discusses for the first time experimentally and theoretically how light confinement arises in planar micromirrors and is of interest for the realisation of chip-based extended microphotonics using open cavities.
Hawking radiation from small black holes at strong coupling and large N
Haddad, Nidal
2013-10-01
In a previous work an approximate static metric was found of a test black string that stretches from the boundary to the horizon of the planar Schwarzschild-AdS5 geometry. This is the gravity dual of the Unruh state for {N}=4, SU(N) super Yang-Mills theory on a four-dimensional Schwarzschild background, at large N and large ’tHooft coupling. We compute the holographic stress tensor of the gravitational solution and it turns out to possess many essential features of the Unruh state for weakly coupled Hawking radiation, such as the appearance of a negative energy density near the black hole horizon and a positive energy density at infinity. It also confirms recent results that at leading order in N, the expectation value of the stress tensor in the Unruh state is finite on both the future and past horizons, and that at this order there are no flux terms as is expected in the black droplet phase.
Energy Technology Data Exchange (ETDEWEB)
Cao, X [Department of Physics and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, 361005 (China); You, J Q; Nori, F [Advanced Science Institute, RIKEN, Wako-shi 351-0198 (Japan); Zheng, H, E-mail: xfcao@xmu.edu.cn [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China)
2011-07-15
We investigate the spontaneous emission (SE) spectrum of a qubit in a lossy resonant cavity. We use neither the rotating-wave approximation nor the Markov approximation. For the weak-coupling case, the SE spectrum of the qubit is a single peak, with its location depending on the spectral density of the qubit environment. Then, the asymmetry (of the location and heights of the two peaks) of the two SE peaks (which are related to the vacuum Rabi splitting) changes as the qubit-cavity coupling increases. Explicitly, for a qubit in a low-frequency intrinsic bath, the height asymmetry of the splitting peaks is enhanced as the qubit-cavity coupling strength increases. However, for a qubit in an Ohmic bath, the height asymmetry of the spectral peaks is inverted compared to the low-frequency bath case. With further increasing the qubit-cavity coupling to the ultra-strong regime, the height asymmetry of the left and right peaks is slightly inverted, which is consistent with the corresponding case of a low-frequency bath. This inversion of the asymmetry arises from the competition between the Ohmic bath and the cavity bath. Therefore, after considering the anti-rotating terms, our results explicitly show how the height asymmetry in the SE spectrum peaks depends on the qubit-cavity coupling and the type of intrinsic noise experienced by the qubit.
Kozin, V. K.; Iorsh, I. V.; Kibis, O. V.; Shelykh, I. A.
2018-01-01
We demonstrate theoretically that a strong high-frequency circularly polarized electromagnetic field can turn a two-dimensional periodic array of interconnected quantum rings into a topological insulator. The elaborated approach is applicable to calculate and analyze the electron energy spectrum of the array, the energy spectrum of the edge states, and the corresponding electronic densities. As a result, the present theory paves the way to optical control of the topological phases in ring-based mesoscopic structures.
Wave failure at strong coupling in intracellular C a2 + signaling system with clustered channels
Li, Xiang; Wu, Yuning; Gao, Xuejuan; Cai, Meichun; Shuai, Jianwei
2018-01-01
As an important intracellular signal, C a2 + ions control diverse cellular functions. In this paper, we discuss the C a2 + signaling with a two-dimensional model in which the inositol 1,4,5-trisphosphate (I P3 ) receptor channels are distributed in clusters on the endoplasmic reticulum membrane. The wave failure at large C a2 + diffusion coupling is discussed in detail in the model. We show that with varying model parameters the wave failure is a robust behavior with either deterministic or stochastic channel dynamics. We suggest that the wave failure should be a general behavior in inhomogeneous diffusing systems with clustered excitable regions and may occur in biological C a2 + signaling systems.
Strongly interacting vector bosons at the CERN LHC Quartic anomalous couplings
Belyaev, A; González-Garciá, M Concepción; Mizukoshi, J K; Novaes, S F; Zacharov, I E
1999-01-01
We analyze the potential of the CERN Large Hadron Collider to study anomalous quartic vector--boson interactions through the production of vector--boson pairs accompanied by jets. In the framework of $SU(2)_L \\otimes U(1)_Y$ chiral Lagrangians, we examine all effective operators of order $p^4$ that lead to new four--gauge--boson interactions but do not alter trilinear vertices. In our analyses, we perform the full tree level calculation of the processes leading to two jets plus vector--boson pairs, $W^+W^-$, $W^\\pm W^\\pm$, $W^\\pm Z$, or $ZZ$, taking properly into account the interference between the standard model and the anomalous contributions. We obtain the bounds that can be placed on the anomalous quartic interactions and we study the strategies to distinguish the possible new couplings.
Exchange bias and major coercivity enhancement in strongly-coupled CuO/Co films
Gamino, M.; de Andrade, A. M. H.; Salazar Cuaila, J. L.; Schmidt, J. E.; Skumryev, V.; Geshev, J.
2018-03-01
The exchange-bias properties of ferromagnetic, either Co or Ni, thin films deposited onto polycrystalline multiferroic CuO are investigated. After field cooling, the CuO/Co magnetization hysteresis loops show exchange bias at temperatures lower than 200 K, while the CuO/Ni system exhibits bias below about 5 K only. It is suggested that the exchange bias of CuO/Co is determined mainly by the magnetization reversal that takes place on the descending branch of the loop. Rather high values of both the interface coupling energy, 0.89 erg/cm2, and coercivity, 2.44 kOe, of the CuO/Co film are obtained at 5 K.
Slater Insulator in Iridate Perovskites with Strong Spin-Orbit Coupling
Energy Technology Data Exchange (ETDEWEB)
Cui, Q.; Cheng, J. -G.; Fan, W.; Taylor, A. E.; Calder, S.; McGuire, M. A.; Yan, J. -Q.; Meyers, D.; Li, X.; Cai, Y. Q.; Jiao, Y. Y.; Choi, Y.; Haskel, D.; Gotou, H.; Uwatoko, Y.; Chakhalian, J.; Christianson, A. D.; Yunoki, S.; Goodenough, J. B.; Zhou, J. -S.
2016-10-20
The perovskite (Pv) SrIrO_{3} is an exotic narrow-band metal owing to a confluence of the strengths of the spin-orbit coupling (SOC) and the electron-electron correlations. It has been proposed that topological and magnetic insulating phases can be achieved by tuning the SOC, Hubbard interactions, and/or lattice symmetry. Here, we report that the substitution of nonmagnetic, isovalent Sn^{4+} for Ir^{4+} in the SrIr_{1-x}Sn_{x}O_{3} perovskites synthesized under high pressure leads to a metal-insulator transition to an antiferromagnetic phase at TN ≥ 225 K. The continuous change of the cell volume as detected by X-ray diffraction and the l-shape transition of the specific heat on cooling through TN demonstrate that the metal-insulator transition is of second-order. Neutron powder diffraction results indicate that the Sn substitution enlarges an octahedral-site distortion that reduces the SOC relative to the spin-spin exchange interaction and results in the type-G AF spin ordering below TN. Measurement of high-temperature magnetic susceptibility shows the evolution of magnetic coupling in the paramagnetic phase typical of weak itinerant-electron magnetism in the Sn-substituted samples. A reduced structural symmetry in the magnetically ordered phase leads to an electron gap opening at the Brillouin zone boundary below TN in the same way as proposed by Slater.
Rocha, Reginaldo C; Brown, Mac G; Londergan, Casey H; Salsman, J Catherine; Kubiak, Clifford P; Shreve, Andrew P
2005-10-13
Resonance Raman spectroelectrochemistry (RR-SEC) at -20 degrees C has been performed on the pyrazine-bridged dimer of mu-oxo-centered trinuclear ruthenium-acetate "clusters"--[(dmap)(CO)(mu-OAc)6(mu3-O)Ru3(mu-L(b))Ru3(mu3-O)(mu-OAc)6(CO)(dmap)]n (where dmap = 4-(dimethylamino)pyridine and L(b) = pyrazine-h4 and pyrazine-d4)-in three oxidation states: n = 0, -1, and -2. In the one-electron reduced, "mixed-valent" state (overall -1 charge and a single odd electron; formal oxidation states [II, II, III]-[III, III, II] on the metal centers), the Raman excitation at 800 nm is resonant with a cluster-to-cluster intervalence charge-transfer (IVCT) band. Under these conditions, scattering enhancement is observed for all four totally symmetric vibrational modes of the bridging pyrazine ligand (nu8a, nu9a, nu1, and nu6a) in the investigated spectral range (100-2000 cm(-1)), and there is no evidence of activity in non-totally symmetric vibrations. Resonantly enhanced Raman peaks related to peripheral pyridyl (dmap) ligand modes and low-frequency features arising from the trigonal Ru3O cluster core and the cluster[Ru]-[N]ligand vibrations were also observed in the spectra of the intermediate-valence (n = -1) cluster dimer. The vibrational assignments and interpretations proposed in this work were reinforced by observation of characteristic isotopic frequency shifts accompanying deuteration of the bridging pyrazine. The results reveal that the fully symmetric (A(g)) vibrational motions of the organic bridge are coupled to the nominally metal cluster-to-metal cluster fast intramolecular electron transfer (ET) and provide validation of the near-delocalized description according to a predicted three-site/three-state (e.g., metal-bridge-metal) vibronic coupling model, in which the important role of the bridging ligand in mediating electronic communication and delocalization between charge centers is explicitly considered. Further compelling evidence supporting an extended five
Farabi, Sarah S; Carley, David W; Quinn, Lauretta
2017-05-01
Glucose variations are common throughout sleep and wakefulness in people with type 1 diabetes mellitus (T1DM). The objective of this investigation was to characterize the time-varying coupling between glucose and unstructured physical activity over a 60-hr period in young adults with T1DM. The hypothesis was that coupling would differ during sleep versus wakefulness and would exhibit circadian variations. Young adults with T1DM treated with an insulin pump participated in the study. Glucose variations were monitored with a continuous glucose monitoring system, and activity was assessed using an activity-monitoring band worn on the nondominant wrist. Simultaneous glucose and physical activity data across a continuous 60-hr period were used for analysis. Wavelet coherence analysis was employed to quantify the coupling between physical activity and glucose. Cosinor analysis was used to assess whether glucose/activity coherence exhibited significant circadian variations. Participants comprised 23 adults, aged 18-30 years, with T1DM. Coherence analysis demonstrated substantial coupling between physical activity and glucose variations during both wakefulness and sleep. For rapid (10-30 min) fluctuations, mean coherence was higher during sleep than wakefulness ( F = 10.86, p = .003). Rapid glucose variations consistently led to changes in activity ( p = .001) during sleep but not during wake. Cosinor analysis revealed significant circadian modulation of glucose/activity coupling, especially for fluctuation periods 2-4 hr. Unstructured physical activity and glucose variations demonstrated strong time- and frequency-dependent coupling over a 60-hr period in young adults with T1DM, with sleep/wake differences and circadian modulation evident in this relationship.
Continuous Time Monte Carlo for Lattice QCD in the Strong Coupling Limit
Unger, Wolfgang
2011-01-01
We present results for lattice QCD with staggered fermions in the limit of infinite gauge coupling, obtained from a worm-type Monte Carlo algorithm on a discrete spatial lattice but with continuous Euclidean time. This is achieved by sending both the anisotropy parameter $\\gamma^2\\simeq a/\\at$ and the number of time-slices $N_\\tau$ to infinity, keeping the ratio $\\gamma^2/N_\\tau \\simeq aT$ fixed. In this limit, ambiguities arising from the anisotropy parameter $\\gamma$ are eliminated and discretization errors usually introduced by a finite temporal lattice extent $\\Nt$ are absent. The obvious gain is that no continuum extrapolation $N_\\tau \\rightarrow \\infty$ has to be carried out. Moreover, the algorithm is faster and the sign problem disappears completely. As a first application, we determine the phase diagram as a function of temperature and real and imaginary baryon chemical potential. We compare our computations with those on lattices with discrete Euclidean time. Discretization errors due to finite $\\Nt...
Bridging the Gap for High-Coherence, Strongly Coupled Superconducting Qubits
Yoder, Jonilyn; Kim, David; Baldo, Peter; Day, Alexandra; Fitch, George; Holihan, Eric; Hover, David; Samach, Gabriel; Weber, Steven; Oliver, William
Crossovers can play a critical role in increasing superconducting qubit device performance, as long as device coherence can be maintained even with the increased fabrication and circuit complexity. Specifically, crossovers can (1) enable a fully-connected ground plane, which reduces spurious modes and crosstalk in the circuit, and (2) increase coupling strength between qubits by facilitating interwoven qubit loops with large mutual inductances. Here we will describe our work at MIT Lincoln Laboratory to integrate superconducting air bridge crossovers into the fabrication of high-coherence capacitively-shunted superconducting flux qubits. We will discuss our process flow for patterning air bridges by resist reflow, and we will describe implementation of air bridges within our circuits. This research was funded in part by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA) and by the Assistant Secretary of Defense for Research and Engineering under Air Force Contract No. FA8721-05-C-0002. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of ODNI, IARPA, or the US Government.
Strong Coupling and Bounds on the Spin-2 Mass in Massive Gravity
Burrage, Clare; Kaloper, Nemanja; Padilla, Antonio
2013-07-01
The de Rham-Gabadadze-Tolley theory of a single massive spin-2 field has a cutoff much below its Planck scale because the extra modes from the massive spin-2 multiplet involve higher derivative self-interactions, controlled by a scale convoluted from its mass. Generically, these correct the propagator by environmental effects. The resulting effective cutoff depends on the environmental parameters and the spin-2 “graviton” mass. Requiring the theory to be perturbative down to O(1)mm, we derive bounds on the mass, corresponding to ≳O(1)meV for the generic case, assuming the coupling to be given by the standard Newton’s constant, and somewhat weaker bounds in cases with fine-tuning. Thus, the theory of a single massive spin-2 can really only be viewed as a theory describing the full nonlinear propagation of a massive spin-2 field on a fixed background and not as an approximation to general relativity.
Li, Guang-Hui; Wang, An-Bang; Feng, Ye; Wang, Yang
2010-07-01
This paper numerically demonstrates synchronization and bidirectional communication without delay line by using two semiconductor lasers with strong mutual injection in a face-to-face configuration. These results show that both of the two lasers' outputs synchronize with their input chaotic carriers. In addition, simulations demonstrate that this kind of synchronization can be used to realize bidirectional communications without delay line. Further studies indicate that within a small deviation in message amplitudes of two sides (±6%), the message can be extracted with signal-noise-ratio more than 10 dB; and the signal-noise-ratio is extremely sensitive to the message rates mismatch of two sides, which may be used as a key of bidirectional communication.
Exploring the physics of superconducting qubits strongly coupled to microwave frequency photons
Energy Technology Data Exchange (ETDEWEB)
Wallraff, Andreas [ETH Zurich (Switzerland)
2013-07-01
Using modern micro and nano-fabrication techniques combined with superconducting materials we realize electronic circuits the properties of which are governed by the laws of quantum mechanics. In such circuits the strong interaction of photons with superconducting quantum two-level systems allows us to probe fundamental quantum properties of light and to develop components for applications in quantum information technology. Here, I present experiments in which we have created and probed entanglement between stationary qubits and microwave photons freely propagating down a transmission line. In these experiments we use superconducting parametric amplifiers realized in our lab to detect both qubit and photon states efficiently. Using similar techniques we aim at demonstrating a deterministic scheme for teleportation of quantum states in a macroscopic system based on superconducting circuits.
International Nuclear Information System (INIS)
Protopapas, P.; Klein, A.
1997-01-01
We review briefly the fundamental equations of a semimicroscopic core-particle coupling method that makes no reference to an intrinsic system of coordinates. We then demonstrate how an intrinsic system can be introduced in the strong coupling limit so as to yield a completely equivalent formulation. It is emphasized that the conventional core-particle coupling calculation introduces a further approximation that avoids what has hitherto been the most time-consuming feature of the full theory, and that this approximation can be introduced either in the intrinsic system, the usual case, or in the laboratory system, our preference. A new algorithm is described for the full theory that largely removes the difference in complexity between the two types of calculation. Comparison of the full and approximate theories for some representative cases provides a basis for the assessment of the accuracy of the traditional approach. We find that for well-deformed nuclei, e.g., 157 Gd and 157 Tb, the core-coupling method and the full theory give similar results. copyright 1997 The American Physical Society
Energy Technology Data Exchange (ETDEWEB)
Chung, Y. D.; Lee, S. Y.; Lee, T. W.; Kim, J. S. [Suwon Science College, Suwon (Korea, Republic of); Lee, C. Y. [Korea Railroad Institute, Uiwang (Korea, Republic of)
2016-03-15
The technology of supplying the electric power by wireless power transfer (WPT) is expected for the next generation power feeding system since it can supply the power to portable devices without any connectors through large air gap. As such a technology based on strongly coupled electromagnetic resonators is possible to deliver the large power and recharge them seamlessly; it has been considered as a noble option to wireless power charging system in the various power applications. Recently, various HTS wires have now been manufactured for demonstrations of transmission cables, motors, MAGLEV, and other electrical power components. However, since the HTS magnets have a lower index n value intrinsically, they are required to be charged from external power system through leads or internal power system. The portable area is limited as well as the cryogen system is bulkier. Thus, we proposed a novel design of wireless power charging system for superconducting HTS magnet (WPC4SM) based on resonance coupling method. As the novel system makes possible a wireless power charging using copper resonance coupled coils, it enables to portable charging conveniently in the superconducting applications. This paper presented the conceptual design and operating characteristics of WPC4SM using different shapes' copper resonance coil. The proposed system consists of four components; RF generator of 370 kHz, copper resonance coupling coils, impedance matching (IM) subsystem and HTS magnet including rectifier system.
Kim, Junyeon; Karube, Shutaro; Chen, Yan-Ting; Kondou, Kouta; Tatara, Gen; Otani, YoshiChika
2016-10-01
Spin-charge conversion induced by spin-orbit coupling (SOC) is attractive topic for alternative magnetization manipulation and involved various novel phenomena. Particularly Bi-based structure draws interest due to its large Rashba-Edelstein effect (REE) at interface between non-magnetic metal and Bi [1]. A recent report showed that spin-to-charge current conversion becomes more efficient when Bi2O3 is employed on behalf of the Bi [2]. Here we report novel type of magnetoresistance (MR) in Co25Fe75/Cu/Bi2O3 multilayer. This novel MR comes from conversion between spin and charge current at Cu/Bi2O3 interface, and distinctive spin transfer torque dependent on magnetization of the ferromagnetic Co25Fe75 layer. A Co25Fe75 (5)/Cu (0-30)/Bi2O3 (20) (unit:nm) multilayer was deposited with electron beam evaporation on shadow masked Si substrate. Hall bar shaped shadow mask was patterned with photo-lithography method. The MR measurement was performed via 4-point probe method with changing magnitude or angle of external field. Note that external field for angle dependent measurement was 6 T to make sure complete saturation of ferromagnetic layer. We found characteristic resistance drop when the magnetization of ferromagnetic layer is parallel to magnetic direction of spin accumulation, which is similar to spin Hall magnetoresistance (SMR) [3,4]. Further discussion will be given. [1] J. C. Rojas Sanchez et al. Nature Comm. 4, 2944 (2013). [2] S. Karube et al. Appl. Phys. Express. 9, 03301 (2016). [3] H. Nakayama et al. Phys. Rev. Lett. 110, 206601 (2013). [4] J. Kim et al. Phys. Rev. Lett. (in press).
International Nuclear Information System (INIS)
Gregori, G.; Hansen, S.B.; Key, M.H.; King, J.; Mackinnon, A.J.; Park, H.; Patel, P.K.; Shepard, R.; Snavely, R.A.; Wilks, S.C.; Glenzer, S.H.
2005-01-01
We have measured high resolution copper Kα spectra from a picosecond high intensity laser produced plasma. By fitting the shape of the experimental spectra with a self-consistent-field model which includes all the relevant line shifts from multiply ionized atoms, we are able to infer time and spatially averaged electron temperatures (T e ) and ionization state (Z) in the foil. Our results show increasing values for T e and Z when the overall mass of the target is reduced. In particular, we measure temperatures in excess of 200 eV with Z ∼ 13-14. For these conditions the ion-ion coupling constant is Λ ii ∼ 8-9, thus suggesting the achievement of a strongly coupled plasma regime
Abazov, V.M.; et al., [Unknown; Ancu, L.S.; de Jong, S.J.; Filthaut, F.; Galea, C.F.; Hegeman, J.G.; Houben, P.; Meijer, M.M.; Svoisky, P.; van den Berg, P.J.; van Leeuwen, W.M.
2009-01-01
We determine the strong coupling constant alpha(s) and its energy dependence from the p(T) dependence of the inclusive jet cross section in pp collisions at s=1.96 TeV. The strong coupling constant is determined over the transverse momentum range 50 < p(T)< 145 GeV. Using perturbative QCD
The topological structures in strongly coupled QGP with chiral fermions on the lattice
Energy Technology Data Exchange (ETDEWEB)
Sharma, Sayantan [Physics Department, Brookhaven National Laboratory, Upton, New York-11973 (United States); Dick, Viktor [Fakultät für Physik, Universität Bielefeld, Universitätstasse 25, D33619 Bielefeld (Germany); Karsch, Frithjof [Physics Department, Brookhaven National Laboratory, Upton, New York-11973 (United States); Fakultät für Physik, Universität Bielefeld, Universitätstasse 25, D33619 Bielefeld (Germany); Laermann, Edwin [Fakultät für Physik, Universität Bielefeld, Universitätstasse 25, D33619 Bielefeld (Germany); Mukherjee, Swagato [Physics Department, Brookhaven National Laboratory, Upton, New York-11973 (United States)
2016-12-15
The nature of chiral phase transition for two flavor QCD is an interesting but unresolved problem. One of the most intriguing issues is whether or not the anomalous U(1) symmetry in the flavor sector is effectively restored along with the chiral symmetry. This may determine the universality class of the chiral phase transition. Since the physics near the chiral phase transition is essentially non-perturbative, we employ first principles lattice techniques to address this issue. We use overlap fermions, which have exact chiral symmetry on the lattice, to probe the anomalous U(1) symmetry violation of 2+1 flavor dynamical QCD configurations with domain wall fermions. The latter also optimally preserves chiral and flavor symmetries on the lattice, since it is known that the remnant chiral symmetry of the light quarks influences the scaling of the chiral condensate in the crossover transition region. We observe that the anomalous U(1) is not effectively restored in the chiral crossover region. We perform a systematic study of the finite size and cut-off effects since the signals of U(1) violation are sensitive to it. We also provide a glimpse of the microscopic topological structures of the QCD medium that are responsible for the strongly interacting nature of the quark gluon plasma phase. We study the effect of these microscopic constituents through our first calculations for the topological susceptibility of QCD at finite temperature, which could be a crucial input for the equation of state for anomalous hydrodynamics.
Strong coupling constant extraction from high-multiplicity $Z+\text{jets}$ observables
Johnson, Mark; Maître, Daniel
2018-01-01
We present a strong coupling constant extraction at next-to-leading order QCD accuracy using ATLAS Z+2,3,4 jets data. This is the first extraction using processes with a dependency on high powers of the coupling constant. We obtain values of the strong coupling constant at the Z mass compatible with the world average and with uncertainties commensurate with other next-to-leading order extractions at hadron colliders. Our most conservative result for the strong coupling constant is αS(MZ)=0.11...
Integrated fiber-mirror ion trap for strong ion-cavity coupling
International Nuclear Information System (INIS)
Brandstätter, B.; Schüppert, K.; Casabone, B.; Friebe, K.; Stute, A.; Northup, T. E.; McClung, A.; Schmidt, P. O.; Deutsch, C.; Reichel, J.; Blatt, R.
2013-01-01
We present and characterize fiber mirrors and a miniaturized ion-trap design developed to integrate a fiber-based Fabry-Perot cavity (FFPC) with a linear Paul trap for use in cavity-QED experiments with trapped ions. Our fiber-mirror fabrication process not only enables the construction of FFPCs with small mode volumes, but also allows us to minimize the influence of the dielectric fiber mirrors on the trapped-ion pseudopotential. We discuss the effect of clipping losses for long FFPCs and the effect of angular and lateral displacements on the coupling efficiencies between cavity and fiber. Optical profilometry allows us to determine the radii of curvature and ellipticities of the fiber mirrors. From finesse measurements, we infer a single-atom cooperativity of up to 12 for FFPCs longer than 200 μm in length; comparison to cavities constructed with reference substrate mirrors produced in the same coating run indicates that our FFPCs have similar scattering losses. We characterize the birefringence of our fiber mirrors, finding that careful fiber-mirror selection enables us to construct FFPCs with degenerate polarization modes. As FFPCs are novel devices, we describe procedures developed for handling, aligning, and cleaning them. We discuss experiments to anneal fiber mirrors and explore the influence of the atmosphere under which annealing occurs on coating losses, finding that annealing under vacuum increases the losses for our reference substrate mirrors. X-ray photoelectron spectroscopy measurements indicate that these losses may be attributable to oxygen depletion in the mirror coating. Special design considerations enable us to introduce a FFPC into a trapped ion setup. Our unique linear Paul trap design provides clearance for such a cavity and is miniaturized to shield trapped ions from the dielectric fiber mirrors. We numerically calculate the trap potential in the absence of fibers. In the experiment additional electrodes can be used to compensate
Brewer, Jasmine; Rajagopal, Krishna; Sadofyev, Andrey; van der Schee, Wilke
2018-02-01
Some of the most important experimentally accessible probes of the quark- gluon plasma (QGP) produced in heavy ion collisions come from the analysis of how the shape and energy of sprays of energetic particles produced within a cone with a specified opening angle (jets) in a hard scattering are modified by their passage through the strongly coupled, liquid, QGP. We model an ensemble of back-to-back dijets for the purpose of gaining a qualitative understanding of how the shapes of the individual jets and the asymmetry in the energy of the pairs of jets in the ensemble are modified by their passage through an expanding cooling droplet of strongly coupled plasma, in the model in a holographic gauge theory that is dual to a 4+1-dimensional black-hole spacetime that is asymptotically anti-de Sitter (AdS). We build our model by constructing an ensemble of strings in the dual gravitational description of the gauge theory. We model QCD jets in vacuum using strings whose endpoints are moving "downward" into the gravitational bulk spacetime with some fixed small angle, an angle that represents the opening angle (ratio of jet mass to jet energy) that the QCD jet would have in vacuum. Such strings must be moving through the gravitational bulk at (close to) the speed of light; they must be (close to) null. This condition does not specify the energy distribution along the string, meaning that it does not specify the shape of the jet being modeled. We study the dynamics of strings that are initially not null and show that strings with a wide range of initial conditions rapidly accelerate and become null and, as they do, develop a similar distribution of their energy density. We use this distribution of the energy density along the string, choose an ensemble of strings whose opening angles and energies are distributed as in perturbative QCD, and show that we can then fix one of the two model parameters such that the mean jet shape for the jets in the ensemble that we have built
Finite-size effect of η-deformed AdS5×S5 at strong coupling
Directory of Open Access Journals (Sweden)
Changrim Ahn
2017-04-01
Full Text Available We compute Lüscher corrections for a giant magnon in the η-deformed (AdS5×S5η using the su(2|2q-invariant S-matrix at strong coupling and compare with the finite-size effect of the corresponding string state, derived previously. We find that these two results match and confirm that the su(2|2q-invariant S-matrix is describing world-sheet excitations of the η-deformed background.
International Nuclear Information System (INIS)
Dahmen, Bernd
1994-01-01
A systematic method to obtain strong coupling expansions for scattering quantities in hamiltonian lattice field theories is presented. I develop the conceptual ideas for the case of the hamiltonian field theory analogue of the Ising model, in d space and one time dimension. The main result is a convergent series representation for the scattering states and the transition matrix. To be explicit, the special cases of d=1 and d=3 spatial dimensions are discussed in detail. I compute the next-to-leading order approximation for the phase shifts. The application of the method to investigate low-energy scattering phenomena in lattice gauge theory and QCD is proposed. ((orig.))
Finite-size effect of η-deformed AdS5 × S5 at strong coupling
Ahn, Changrim
2017-04-01
We compute Lüscher corrections for a giant magnon in the η-deformed (AdS5×S5)η using the su(2 | 2) q-invariant S-matrix at strong coupling and compare with the finite-size effect of the corresponding string state, derived previously. We find that these two results match and confirm that the su(2 | 2) q-invariant S-matrix is describing world-sheet excitations of the η-deformed background.
Ricci solitons, Ricci flow and strongly coupled CFT in the Schwarzschild Unruh or Boulware vacua
Figueras, Pau; Lucietti, James; Wiseman, Toby
2011-11-01
The elliptic Einstein-DeTurck equation may be used to numerically find Einstein metrics on Riemannian manifolds. Static Lorentzian Einstein metrics are considered by analytically continuing to Euclidean time. The Ricci-DeTurck flow is a constructive algorithm to solve this equation, and is simple to implement when the solution is a stable fixed point, the only complication being that Ricci solitons may exist which are not Einstein. Here we extend previous work to consider the Einstein-DeTurck equation for Riemannian manifolds with boundaries, and those that continue to static Lorentzian spacetimes which are asymptotically flat, Kaluza-Klein, locally AdS or have extremal horizons. Using a maximum principle, we prove that Ricci solitons do not exist in these cases and so any solution is Einstein. We also argue that the Ricci-DeTurck flow preserves these classes of manifolds. As an example, we simulate the Ricci-DeTurck flow for a manifold with asymptotics relevant for AdS5/CFT4. Our maximum principle dictates that there are no soliton solutions, and we give strong numerical evidence that there exists a stable fixed point of the flow which continues to a smooth static Lorentzian Einstein metric. Our asymptotics are such that this describes the classical gravity dual relevant for the CFT on a Schwarzschild background in either the Unruh or Boulware vacua. It determines the leading O(N2c) part of the CFT stress tensor, which interestingly is regular on both the future and past Schwarzschild horizons.
Ricci solitons, Ricci flow and strongly coupled CFT in the Schwarzschild Unruh or Boulware vacua
Energy Technology Data Exchange (ETDEWEB)
Figueras, Pau [DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Lucietti, James [School of Mathematics and Maxwell Institute for Mathematical Sciences, University of Edinburgh, King' s Buildings, Edinburgh EH9 3JZ (United Kingdom); Wiseman, Toby, E-mail: t.wiseman@imperial.ac.uk [Theoretical Physics Group, Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom)
2011-11-07
The elliptic Einstein-DeTurck equation may be used to numerically find Einstein metrics on Riemannian manifolds. Static Lorentzian Einstein metrics are considered by analytically continuing to Euclidean time. The Ricci-DeTurck flow is a constructive algorithm to solve this equation, and is simple to implement when the solution is a stable fixed point, the only complication being that Ricci solitons may exist which are not Einstein. Here we extend previous work to consider the Einstein-DeTurck equation for Riemannian manifolds with boundaries, and those that continue to static Lorentzian spacetimes which are asymptotically flat, Kaluza-Klein, locally AdS or have extremal horizons. Using a maximum principle, we prove that Ricci solitons do not exist in these cases and so any solution is Einstein. We also argue that the Ricci-DeTurck flow preserves these classes of manifolds. As an example, we simulate the Ricci-DeTurck flow for a manifold with asymptotics relevant for AdS{sub 5}/CFT{sub 4}. Our maximum principle dictates that there are no soliton solutions, and we give strong numerical evidence that there exists a stable fixed point of the flow which continues to a smooth static Lorentzian Einstein metric. Our asymptotics are such that this describes the classical gravity dual relevant for the CFT on a Schwarzschild background in either the Unruh or Boulware vacua. It determines the leading O(N{sup 2}{sub c}) part of the CFT stress tensor, which interestingly is regular on both the future and past Schwarzschild horizons. (paper)
Strongly coupled coulomb systems of dust particles in traps and plasmas
International Nuclear Information System (INIS)
Petrov, O.F.; Fortov, V.E.
2011-01-01
Complete text of publication follows. After first experimental observations of ordered structures of dust particles in rf and dc gas discharges, similar dusty plasma structures are frequently considered as a macroscopic physical model of coupled Coulomb systems (SCCS), which can visually be observed. Using such structures of charged dust particles, one can investigate the processes of phase transitions, waves, and instabilities on kinetic levels. One of the central problems associated with experimental studies of stable SCCS is that of ensuring the levitation of charged particles. The levitation of dust particles in gas discharges is provided by the interaction of the particle charge with electric field. For confinement and investigation of SCCS of charged dust particles, we propose to use a trap based on the known possibility of the levitation of diamagnetic bodies in a nonuniform steady-state magnetic field. An experimental setup is described, which is capable of forming and confining clusters of charge graphite particles sized 100 to 300 μm in magnetic field B∼1 T and |V-barB| ∼10 T/cm. It is inferred that it will be possible to form stable 3d dust structures containing several thousand particles under terrestrial conditions by using more intensive magnetic fields B > 10 T. Less intensive magnetic fields (B ∼ 0.1 T, |V-barB| ∼ 0.1 T/cm) will be required for studying analogous structures under microgravity conditions. The superhigh charging of dust particles under direct stimulation by an electron beam is experimentally investigated. The energy of beam electrons amounts to 25 keV, with the typical diameter of dust particles employed in the experiment of 100 μm. The charge acquired by a dust particle amounts to 5·10 7 electron charges, which is more than two orders of magnitude higher than the values of the charge of dust particles in gas discharges. A technique for analyzing the pair interaction forces between particles in nonideal dissipative systems
National evaluation of Naesudden 2, NEON
Energy Technology Data Exchange (ETDEWEB)
Tunell, G. [Vattenfall Utveckling AB, Aelvkarleby (Sweden); Andersson, Anders; Olsson, Goeran [Vattenfall AB, Klintehamn (Sweden); Ronsten, G. [Aeronautical Research Inst. of Sweden, Bromma (Sweden); Ganander, H. [Teknikgruppen AB, Sollentuna (Sweden); Goeransson, Bengt [Kvaerner Turbin AB, Kristinehamn (Sweden); Simonsson, B. [KM Akustikbyraan, Solna (Sweden)
1996-12-01
Vattenfall, the main electric utility in Sweden, is operating the Naesudden II turbine (3 MW, diam. 80 m) which was erected in October 1992 on the island of Gotland in the Baltic Sea. An evaluation program (National Evaluation of Naesudden II, NEON) is carried out by Vattenfall in co-operation with FFA, Teknikgruppen, Kvaerner Turbin and others. This paper presents results from the evaluation of power production, availability, power performance, structural behaviour, sub-system performance, and noise emission. Comparisons with the `sister` machine Aeolus II in Wilhelmshaven, Germany, are carried out in a research program CAN (Comparison Aeolus II - Naesudden II) within WEGA II. 7 refs, 14 figs, 4 tabs
Photoelectron and ICD electron angular distributions from fixed-in-space neon dimers
Energy Technology Data Exchange (ETDEWEB)
Jahnke, T [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Czasch, A [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Schoeffler, M [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Schoessler, S [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Kaesz, M [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Titze, J [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Kreidi, K [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Grisenti, R E [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Staudte, A [Steacie Institute for Molecular Sciences, 100 Sussex Drive, Ottawa (Canada); Jagutzki, O [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Schmidt, L Ph H [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Semenov, S K [State University of Aerospace Instrumentation, 190000 St. Petersburg (Russian Federation); Cherepkov, N A [State University of Aerospace Instrumentation, 190000 St. Petersburg (Russian Federation); Schmidt-Boecking, H [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany); Doerner, R [Institut fuer Kernphysik, J W Goethe-Universitaet Frankfurt am Main, Max-von-Laue-Str. 1, D-60438 Frankfurt (Germany)
2007-07-07
We report on molecular frame angular distributions of 2s photoelectrons and electrons emitted by interatomic Coulombic decay from neon dimers. We found that the measured angular distribution of the photoelectron strongly depends on the environment of the cluster. The experimental results are in excellent agreement with frozen core Hartree-Fock calculations. The ICD electrons show slight variations in their angular distribution for different kinetic energies.
NEON terrestrial field observations: designing continental scale, standardized sampling
R. H. Kao; C.M. Gibson; R. E. Gallery; C. L. Meier; D. T. Barnett; K. M. Docherty; K. K. Blevins; P. D. Travers; E. Azuaje; Y. P. Springer; K. M. Thibault; V. J. McKenzie; M. Keller; L. F. Alves; E. L. S. Hinckley; J. Parnell; D. Schimel
2012-01-01
Rapid changes in climate and land use and the resulting shifts in species distributions and ecosystem functions have motivated the development of the National Ecological Observatory Network (NEON). Integrating across spatial scales from ground sampling to remote sensing, NEON will provide data for users to address ecological responses to changes in climate, land use,...
Manufacturing cycle for pure neon-helium mixture production
International Nuclear Information System (INIS)
Batrakov, B.P.; Kravchenko, V.A.
1980-01-01
The manufacturing cycle for pure neon-helium mixture production with JA-300 nitrogen air distributing device has been developed. Gas mixture containing 2-3% of neon-helium mixture (the rest is mainly nitrogen 96-97%) is selected out of the cover of the JA-300 column condensator and enters the deflegmator under the 2.3-2.5 atm. pressure. The diflegmator presents a heat exchange apparatus in which at 78 K liquid nitrogen the condensation of nitrogen from the mixture of gases entering from the JA-300 column takes place. The enriched gas mixture containing 65-70% of neon-helium mixture and 30-35% of nitrogen goes out from the deflegmator. This enriched neon-helium mixture enters the gasgoeder for impure (65-70%) neon-helium mixture. Full cleaning of-neon helium mixture of nitrogen is performed by means of an adsorber. As adsorbent an activated coal has been used. Adsorption occurs at the 78 K temperature of liquid nitrogen and pressure P=0.1 atm. As activated coal cooled down to nitrogen temperature adsorbs nitrogen better than neon and helium, the nitrogen from the mixture is completely adsorbed. Pure neon-helium mixture from the adsorber comes into a separate gasgolder. In one campaign the cycle allows obtaining 2 m 3 of the mixture. The mixture contains 0.14% of nitrogen, 0.01% of oxygen and 0.06% of hydrogen
Charge transmission through liquid neon and helium surfaces
Energy Technology Data Exchange (ETDEWEB)
Galea, R [Nevis Laboratories, Columbia University, 136 South Broadway, P.O.Box 137, Irvington, NY, 10533 (United States); Dodd, J [Nevis Laboratories, Columbia University, 136 South Broadway, P.O.Box 137, Irvington, NY, 10533 (United States); Leltchouk, M [Nevis Laboratories, Columbia University, 136 South Broadway, P.O.Box 137, Irvington, NY, 10533 (United States); Willis, W [Nevis Laboratories, Columbia University, 136 South Broadway, P.O.Box 137, Irvington, NY, 10533 (United States); Rehak, P [Brookhaven National Laboratory, P.O. Box 5000, Upton, NY, 11973 (United States); Tcherniatine, V [Brookhaven National Laboratory, P.O. Box 5000, Upton, NY, 11973 (United States)
2007-04-15
The transmission of charges through liquid neon and helium surfaces was studied. It was found that the penetration of charges from the liquid to the gas phase is more complex than a simple barrier penetration. The effective surface trapping times of localized electrons in liquid neon is much longer than previously measured.
Charge transmission through liquid neon and helium surfaces
Galea, R.; Dodd, J.; Leltchouk, M.; Willis, W.; Rehak, P.; Tcherniatine, V.
2007-04-01
The transmission of charges through liquid neon and helium surfaces was studied. It was found that the penetration of charges from the liquid to the gas phase is more complex than a simple barrier penetration. The effective surface trapping times of localized electrons in liquid neon is much longer than previously measured.
Directory of Open Access Journals (Sweden)
A. Stockklauser
2017-03-01
Full Text Available The strong coupling limit of cavity quantum electrodynamics (QED implies the capability of a matterlike quantum system to coherently transform an individual excitation into a single photon within a resonant structure. This not only enables essential processes required for quantum information processing but also allows for fundamental studies of matter-light interaction. In this work, we demonstrate strong coupling between the charge degree of freedom in a gate-defined GaAs double quantum dot (DQD and a frequency-tunable high impedance resonator realized using an array of superconducting quantum interference devices. In the resonant regime, we resolve the vacuum Rabi mode splitting of size 2g/2π=238 MHz at a resonator linewidth κ/2π=12 MHz and a DQD charge qubit decoherence rate of γ_{2}/2π=40 MHz extracted independently from microwave spectroscopy in the dispersive regime. Our measurements indicate a viable path towards using circuit-based cavity QED for quantum information processing in semiconductor nanostructures.
Effective potential in the strong-coupling lattice QCD with next-to-next-to-learning order effects
International Nuclear Information System (INIS)
Nakano, Takashi Z.; Miura, Kohtaroh; Ohnishi, Akira
2010-01-01
We derive an analytic expression of the effective potential at finite temperature (T) and chemical potential (μ) in the strong-coupling lattice QCD for color SU(3) including next-to-next-to-leading order (NNLO) effects in the strong coupling expansion. NNLO effective action terms are systematically evaluated in the leading order of the large dimensional (1/d) expansion, and are found to come from some types of connected two-plaquette configurations. We apply the extended Hubbard-Stratonovich transformation and a gluonic-dressed fermion technique to the effective action, and obtain the effective potential as a function of T, μ, and two order parameters: chiral condensate and vector potential field. The next-to-leading order (NLO) and NNLO effects result in modifications of the wave function renormalization factor, quark mass, and chemical potential. We find that T c,μ =0 and μ c,T =0 are similar to the NLO results, whereas the position of the critical point is sensitive to NNLO corrections. (author)
Chesler, Paul M.
We study dynamics in conformal field theories with gravitational duals. Attention is focused on heavy and light quark jets as well as far-from-equilibrium dynamics. The stress-energy tensor of a heavy quark moving through a strongly coupled N = 4 supersymmetric Yang-Mills plasma is evaluated using gauge/gravity duality. The accuracy with which the resulting wake, in position space, is reproduced by hydrodynamics is examined. Remarkable agreement is found between hydrodynamics and the complete result down to distances less than 2/ T away from the quark. We also compute the penetration depth of a light quark moving through a N = 4 supersymmetric Yang-Mills plasma using a combination of analytic and numerical techniques. We find that the maximum distance a quark with energy E can travel through a plasma is given by Dxmax E= C/T E/Tl 1/3 with C ≈ 0.5. For the study of dynamics far-from-equilibrium, we consider the creation and evolution of boost invariant anisotropic, strongly coupled conformal plasma. In the dual gravitational description, this corresponds to horizon formation in a geometry driven to be anisotropic by a time-dependent change in boundary conditions.
CMS Collaboration
2013-01-01
The recent CMS measurement of the inclusive jet cross section at 7~TeV extends the accessible phase space in jet transverse momentum up to 2 TeV and ranges up to 2.5 in absolute jet rapidity. At the same time the experimental uncertainties are smaller than in previous publications such that these data constrain the parton distribution functions of the proton, notably for the gluon at high fractions of the proton momentum, and provide valuable input to determine the strong coupling at high momentum scales. The impact on the extraction of the parton distribution functions is investigated. Using predictions from theory at next-to-leading order, complemented with electroweak corrections, the strong coupling constant is determined from the inclusive jet cross section to be $\\alpha_S(M_Z) = 0.1185 \\pm 0.0019\\,\\mathrm{(exp.)} \\pm 0.0028\\,\\mathrm{(\\mathrm{PDF})} \\pm 0.0004\\,\\mathrm{(\\mathrm{NP})} ^{+0.0055}_{-0.0022}\\,\\mathrm{(\\mathrm{scale})}$, which is in agreement with the world average.
Shang, Jingwei; Yamashita, Toru; Zhai, Yun; Nakano, Yumiko; Morihara, Ryuta; Fukui, Yusuke; Hishikawa, Nozomi; Ohta, Yasuyuki; Abe, Koji
2016-03-05
Although chronic cerebral hypoperfusion (CCH) may affect Alzheimer's disease (AD) pathogenesis, the mechanism remains elusive. In the present study, we investigated the role of CCH on an AD mouse model in neurovascular unit, cerebrovascular remodeling, and neurovascular trophic coupling. Moreover, examined protective effect of galantamine. Alzheimer's disease transgenic mice (APP23) were subjected to bilateral common carotid arteries stenosis with ameroid constrictors for slowly progressive cerebral hypoperfusion. CCH exacerbated neuronal loss and decrease of α7 subunit of nicotinic acetylcholine receptors (α7-nAChRs) expression in hippocampus and thalamus at 12 months. Meanwhile, CCH greatly induced advanced glycation end products expression, and blood-brain barrier leakage through observing IgG and MMP9 expressions. Furthermore, a significant number of dramatic enlarged cerebral vessels with remodeling, BDNF/TrkB decreased in neurovascular trophic coupling. The present study demonstrated that CCH strongly enhanced primary AD pathology including neurodegeneration, neurovascular unit disruption, cerebrovascular remodeling and neurovascular trophic coupling damage in AD mice, and that galantamine treatment greatly ameliorated such neuropathologic abnormalities.
Watanabe, Norihiro; Blucher, Guido; Cacace, Mauro; Kolditz, Olaf
2016-04-01
A robust and computationally efficient solution is important for 3D modelling of EGS reservoirs. This is particularly the case when the reservoir model includes hydraulic conduits such as induced or natural fractures, fault zones, and wellbore open-hole sections. The existence of such hydraulic conduits results in heterogeneous flow fields and in a strengthened coupling between fluid flow and heat transport processes via temperature dependent fluid properties (e.g. density and viscosity). A commonly employed partitioned solution (or operator-splitting solution) may not robustly work for such strongly coupled problems its applicability being limited by small time step sizes (e.g. 5-10 days) whereas the processes have to be simulated for 10-100 years. To overcome this limitation, an alternative approach is desired which can guarantee a robust solution of the coupled problem with minor constraints on time step sizes. In this work, we present a Newton-Raphson based monolithic coupling approach implemented in the OpenGeoSys simulator (OGS) combined with the Portable, Extensible Toolkit for Scientific Computation (PETSc) library. The PETSc library is used for both linear and nonlinear solvers as well as MPI-based parallel computations. The suggested method has been tested by application to the 3D reservoir site of Groß Schönebeck, in northern Germany. Results show that the exact Newton-Raphson approach can also be limited to small time step sizes (e.g. one day) due to slight oscillations in the temperature field. The usage of a line search technique and modification of the Jacobian matrix were necessary to achieve robust convergence of the nonlinear solution. For the studied example, the proposed monolithic approach worked even with a very large time step size of 3.5 years.
Myasnikova, A. E.; Zhileeva, E. A.; Moseykin, D. V.
2018-03-01
An approach to considering systems with a high concentration of correlated carriers and strong long-range electron–phonon interaction and to calculating the high-energy part of the angle-resolved photoemission spectroscopy (ARPES) spectra of such systems is suggested. Joint relaxation of strongly coupled fields—a field of correlated electrons and phonon field—after photoemission is studied to clarify the nature of characteristic features observed in the high-energy part of the ARPES spectra of cuprate superconductors. Such relaxation occurs in systems with strong predominantly long-range electron–phonon interaction at sufficiently high carrier concentration due to the coexistence of autolocalized and delocalized carriers. A simple method to calculate analytically a high-energy part of the ARPES spectrum arising is proposed. It takes advantage of using the coherent states basis for the phonon field in the polaron and bipolaron states. The approach suggested yields all the high-energy spectral features like broad Gaussian band and regions of ‘vertical dispersion’ being in good quantitative agreement with the experiments on cuprates at any doping with both types of carriers. Demonstrated coexistence of autolocalized and delocalized carriers in superconducting cuprates changes the idea about their ground state above the superconducting transition temperature that is important for understanding transport and magnetic properties. High density of large-radius autolocalized carriers revealed may be a key to the explanation of charge ordering in doped cuprates.
NEON: Contributing continental-scale long-term environmental data for the benefit of society
Wee, B.; Aulenbach, S.
2011-12-01
The National Ecological Observatory Network (NEON) is a NSF funded national investment in physical and information infrastructure. Large-scale environmental changes pose challenges that straddle environmental, economic, and social boundaries. As we develop climate adaptation strategies at the Federal, state, local, and tribal levels, accessible and usable data are essential for implementing actions that are informed by the best available information. NEON's goal is to enable understanding and forecasting of the impacts of climate change, land use change and invasive species on continental-scale ecology by providing physical and information infrastructure. The NEON framework will take standardized, long-term, coordinated measurements of related environmental variables at each of its 62 sites across the nation. These observations, collected by automated instruments, field crews, and airborne instruments, will be processed into more than 700 data products that are provided freely over the web to support research, education, and environmental management. NEON is envisioned to be an integral component of an interoperable ecosystem of credible data and information sources. Other members of this information ecosystem include Federal, commercial, and non-profit entities. NEON is actively involved with the interoperability community via forums like the Foundation for Earth Science Information Partners and the USGS Community for Data Integration in a collective effort to identify the technical standards, best practices, and organizational principles that enable the emergence of such an information ecosystem. These forums have proven to be effective innovation engines for the experimentation of new techniques that evolve into emergent standards. These standards are, for the most part, discipline agnostic. It is becoming increasingly evident that we need to include socio-economic and public health data sources in interoperability initiatives, because the dynamics of coupled
Aktas, A.; Andreev, V.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Beckingham, M.; Begzsuren, K.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J.C.; Boenig, M.-O.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Bruncko, D.; Busser, F.W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cantun Avila, K.B.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Cholewa, A.; Contreras, J.G.; Coughlan, J.A.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Daum, K.; Deak, M.; de Boer, Y.; Delcourt, B.; Del Degan, M.; Delvax, J.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, Guenter; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkiewicz, A.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Gayler, J.; Ghazaryan, Samvel; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Gouzevitch, M.; Grab, C.; Greenshaw, T.; Grell, B.R.; Grindhammer, G.; Habib, S.; Haidt, D.; Hansson, M.; Heinzelmann, G.; Helebrant, C.; Henderson, R.C.W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Jacquet, M.; Janssen, M.E.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jung, Andreas Werner; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, Christian M.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knutsson, A.; Korbel, V.; Kostka, P.; Kraemer, M.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Landon, M.P.J.; Lange, W.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Li, G.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lytkin, L.; Makankine, A.; Malinovski, E.; Marage, P.; Marti, Ll.; Martisikova, M.; Martyn, H.-U.; Maxfield, S.J.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Muller, K.; Murin, P.; Nankov, K.; Naroska, B.; Naumann, Th.; Newman, Paul R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G.D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Picuric, I.; Piec, S.; Pitzl, D.; Placakyte, R.; Polifka, R.; Povh, B.; Preda, T.; Prideaux, P.; Radescu, V.; Rahmat, A.J.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R.N.; Sheviakov, I.; Shtarkov, L.N.; Sloan, T.; Smiljanic, Ivan; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Staykova, Z.; Steder, M.; Stella, B.; Stiewe, J.; Straumann, U.; Sunar, D.; Sykora, T.; Tchoulakov, V.; Thompson, G.; Thompson, P.D.; Toll, T.; Tomasz, F.; Tran, T.H.; Traynor, D.; Trinh, T.N.; Truol, P.; Tsakov, I.; Tseepeldorj, B.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Utkin, D.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Vinokurova, S.; Volchinski, V.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wissing, Ch.; Wolf, R.; Wunsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y.C.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.
2007-01-01
Inclusive jet production is studied in neutral current deep-inelastic positron-proton scattering at large four momentum transfer squared Q^2>150 GeV^2 with the H1 detector at HERA. Single and double differential inclusive jet cross sections are measured as a function of Q^2 and of the transverse energy E_T of the jets in the Breit frame. The measurements are found to be well described by calculations at next-to-leading order in perturbative QCD. The running of the strong coupling is demonstrated and the value of alpha_s(M_Z) is determined. The ratio of the inclusive jet cross section to the inclusive neutral current cross section is also measured and used to extract a precise value for alpha_s(M_Z)=0.1193+/-0.0014(exp.)^{+0.0047}_{-0.0030}(th.)+/-0.0016(pdf).
Abbiendi, G.; Akesson, P.F.; Alexander, G.; Anagnostou, G.; Anderson, K.J.; Asai, S.; Axen, D.; Bailey, I.; Barberio, E.; Barillari, T.; Barlow, R.J.; Batley, R.J.; Bechtle, P.; Behnke, T.; Bell, Kenneth Watson; Bell, P.J.; Bella, G.; Bellerive, A.; Benelli, G.; Bethke, S.; Biebel, O.; Boeriu, O.; Bock, P.; Boutemeur, M.; Braibant, S.; Brown, Robert M.; Burckhart, H.J.; Campana, S.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, D.G.; Ciocca, C.; Csilling, A.; Cuffiani, M.; Dado, S.; De Roeck, A.; De Wolf, E.A.; Desch, K.; Dienes, B.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Etzion, E.; Fabbri, F.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Gagnon, P.; Gary, John William; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Giunta, Marina; Goldberg, J.; Gross, E.; Grunhaus, J.; Gruwe, M.; Gunther, P.O.; Gupta, A.; Hajdu, C.; Hamann, M.; Hanson, G.G.; Harel, A.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herten, G.; Heuer, R.D.; Hill, J.C.; Horvath, D.; Igo-Kemenes, P.; Ishii, K.; Jeremie, H.; Jovanovic, P.; Junk, T.R.; Kanzaki, J.; Karlen, D.; Kawagoe, K.; Kawamoto, T.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kluth, S.; Kobayashi, T.; Kobel, M.; Komamiya, S.; Kramer, T.; Krasznahorkay, A.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kupper, M.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lellouch, D.; Lettso, J.; Levinson, L.; Lillich, J.; Lloyd, S.L.; Loebinger, F.K.; Lu, J.; Ludwig, A.; Ludwig, J.; Mader, W.; Marcellini, S.; Martin, A.J.; Mashimo, T.; Mattig, Peter; McKenna, J.; McPherson, R.A.; Meijers, F.; Menges, W.; Merritt, F.S.; Mes, H.; Meyer, Niels T.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mohr, W.; Mori, T.; Mutter, A.; Nagai, K.; Nakamura, I.; Nanjo, H.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oh, A.; Oreglia, M.J.; Orito, S.; Pahl, C.; Pasztor, G.; Pater, J.R.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Pooth, O.; Przybycien, M.; Quadt, A.; Rabbertz, K.; Rembser, C.; Renkel, P.; Roney, J.M.; Rossi, A.M.; Rozen, Y.; Runge, K.; Sachs, K.; Saeki, T.; Sarkisyan, E.K.G.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schorner-Sadenius, T.; Schroder, Matthias; Schumacher, M.; Seuster, R.; Shears, T.G.; Shen, B.C.; Sherwood, P.; Skuja, A.; Smith, A.M.; Sobie, R.; Soldner-Rembold, S.; Spano, F.; Stahl, A.; Strom, David M.; Strohmer, R.; Tarem, S.; Tasevsky, M.; Teuscher, R.; Thomson, M.A.; Torrence, E.; Toya, D.; Tran, P.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Ujvari, B.; Vollmer, C.F.; Vannerem, P.; Vertesi, R.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wilson, G.W.; Wilson, J.A.; Wolf, G.; Wyatt, T.R.; Yamashita, S.; Zer-Zion, D.; Zivkovic, Lidija
2006-01-01
Data from e+e- annihilation into hadrons at centre-of-mass energies between 91 GeV and 209 GeV collected with the OPAL detector at LEP, are used to study the four-jet rate as a function of the Durham algorithm resolution parameter ycut. The four-jet rate is compared to next-to-leading order calculations that include the resummation of large logarithms. The strong coupling measured from the four-jet rate is alphas(Mz0)= 0.1182+-0.0003(stat.)+-0.0015(exp.)+-0.0011(had.)+-0.0012(scale)+-0.0013(mass) in agreement with the world average. Next-to-leading order fits to the D-parameter and thrust minor event-shape observables are also performed for the first time. We find consistent results, but with significantly larger theoretical uncertainties.
Gor'kov, Lev P.
2012-04-01
We consider a single band of conduction electrons interacting with displacements of the transitional ions. In the classical regime strong enough coupling transforms the harmonic elastic energy for an ion to the one of the well with two deep minima, so that the system is described in terms of Ising spins. Intersite interactions order spins at lower temperatures. Extension to the quantum regime is discussed. Below the charge density wave (CDW) transition the energy spectrum of electrons remains metallic because the structural vector Q and the Fermi surface sizes are not related. Large values of the CDW gap seen in the tunneling experiments correspond to the energy of the minima in the electron-ion two-well complex. The gap is defined through the density of states inside the electronic bands below the CDW transition. We focus mainly on electronic properties of transition-metal dichalcogenides.
Vafaee, A.; Khorramian, A.
2017-11-01
In this QCD analysis, we investigate the impact of recent measurements of heavy-flavor charm and beauty cross sections data sets on the simultaneous determination of Parton Distribution Functions (PDFs) and the strong coupling, αs(M2Z). We perform three different fits based on Variable-Flavour Number Scheme (VFNS) at the Leading Order (LO) and Next-to-Leading Order (NLO) and choose the full HERA run I and II combined data as a new measurement of inclusive Deep Inelastic Scattering (DIS) cross sections for our base data set. We show that including charm and beauty cross sections data reduces the uncertainty of gluon distribution and improves the fit quality up to 4.1% from leading order to next-to-leading order and up to 1.7% for only NLO without and with beauty and charm data contributions.
Llorente Merino, Javier; The ATLAS collaboration
2018-01-01
A measurement of transverse energy--energy correlations and its asymmetry in $pp$ collisions recorded by the ATLAS detector at the LHC at $\\sqrt{s} = 8$ TeV is presented. The results are intepreted as a precision test of Quantum Chromodynamics, used to determine the strong coupling constant $\\alpha_s(m_Z)$ and to test asymptotic freedom up to scales close to 1 TeV. A global fit to the transverse energy--energy correlation distributions yields $\\alpha_{\\mathrm{s}}(m_Z) = 0.1162 \\pm 0.0011 \\mbox{ (exp.)}^{+0.0084}_{-0.0070} \\mbox{ (theo.)}$, while a global fit to the asymmetry distributions yields a value of $\\alpha_{\\mathrm{s}}(m_Z) = 0.1196 \\pm 0.0013 \\mbox{ (exp.)}^{+0.0075}_{-0.0045} \\mbox{ (theo.)}$.
Scuri, Giovanni; Zhou, You; High, Alexander; Dibos, Alan; de Greve, Kristiaan; Polking, Mark; Juaregui, Luis; Wild, Dominik; Joe, Andrew; Pistunova, Kateryna; Lukin, Mikhail; Kim, Philip; Park, Hongkun
Two-dimensional transition-metal dichalcogenide (TMDC) monolayers exhibit direct bandgap excitons with large binding energy. The optical response of TMDCs is electrically tunable over a broad wavelength range, making these 2D materials promising candidates for optoelectronic devices. In this work, we enhance exciton-plasmon coupling by embedding a single layer of tungsten diselenide (WSe2) into a plasmonic crystal cavity, which confines surface plasmon polaritons in an analogous manner to photonic crystal cavities. We observe strong light-matter interactions and the formation of microcavity polaritons when the cavity mode is on resonance with the exciton absorption in WSe2. Using the electrostatically controllable response of such excitons, we also demonstrate tunable vacuum Rabi splitting in such a system.
Bruch, Anton; Lewenkopf, Caio; von Oppen, Felix
2018-03-01
We develop a Landauer-Büttiker theory of entropy evolution in time-dependent, strongly coupled electron systems. The formalism naturally avoids the problem of the system-bath distinction by defining the entropy current in the attached leads. This current can then be used to infer changes of the entropy of the system which we refer to as the inside-outside duality. We carry out this program in an adiabatic expansion up to first order beyond the quasistatic limit. When combined with particle and energy currents, as well as the work required to change an external potential, our formalism provides a full thermodynamic description, applicable to arbitrary noninteracting electron systems in contact with reservoirs. This provides a clear understanding of the relation between heat and entropy currents generated by time-dependent potentials and their connection to the occurring dissipation.
Sieber, Georg; Rabbertz, Klaus
This thesis presents the sensitivity study of PDFs and $\\alpha_\\mathrm{S}$ to the inclusive jet cross section at a center-of-mass energy of $\\sqrt{s}$ = 7 TeV. The data corresponds to an integrated luminosity of 5 fb$^{-1}$ collected with the CMS detector in 2011. Next-to-leading order calculations have been compared to the measurement and found agreement within uncertainties. The PDF sensitivity has been studied using the HERAFitter framework. It was found that the inclusive jet cross section constrains the quark and gluon PDFs in the high-$x$ region and reduces the PDF uncertainties. Furthermore the strong coupling has been extracted using fixed global PDF sets.
International Nuclear Information System (INIS)
Behrend, H.J.; Chen, C.; Fenner, H.; Schachter, M.J.; Schroeder, V.; Sindt, H.; D'Agostini, G.; Apel, W.D.; Banerjee, S.; Bodenkamp, J.; Chrobaczek, D.; Engler, J.; Fluegge, G.; Fries, D.C.; Fues, W.; Gamerdinger, K.; Hopp, G.; Kuester, H.; Mueller, H.; Randoll, H.; Schmidt, G.; Schneider, H.; Boer, W. de; Buschhorn, G.; Grindhammer, G.; Grosse-Wiesmann, P.; Gunderson, B.; Kiesling, C.; Kotthaus, R.; Kruse, U.; Lierl, H.; Lueers, D.; Oberlack, H.; Schacht, P.; Colas, P.; Cordier, A.; Davier, M.; Fournier, D.; Grivaz, J.F.; Haissinski, J.; Journe, V.; Klarsfeld, A.; Laplanche, F.; Le Diberder, F.; Mallik, U.; Veillet, J.J.; Field, J.H.; George, R.; Goldberg, M.; Grossetete, B.; Hamon, O.; Kapusta, F.; Kovacs, F.; London, G.; Poggioli, L.; Rivoal, M.; Aleksan, R.; Bouchez, J.; Carnesecchi, G.; Cozzika, G.; Ducros, Y.; Gaidot, A.; Jadach, S.; Lavagne, Y.; Pamela, J.; Pansart, J.P.; Pierre, F.
1983-01-01
Hadronic events obtained with the CELLO detector at PETRA were compared with first-order QCD predictions using two different models for the fragmentation of quarks and gluons, the Hoyer model and the Lund model. Both models are in reasonable agreement with the data, although they do not completely reproduce the details of many distributions. Several methods have been applied to determine the strong coupling constant αsub(s). Although within one model the value of αsub(s) varies by 20% among the different methods, the values determined using the Lund model are 30% or more larger (depending on the method used) than the values determined with the Hoyer model. Our results using the Hoyer model are in agreement with previous results based on this approach. (orig.)
Baule, A; Evans, R M L; Olmsted, P D
2006-12-01
We revisit the paradigm of an ideal gas under isothermal conditions. A moving piston performs work on an ideal gas in a container that is strongly coupled to a heat reservoir. The thermal coupling is modeled by stochastic scattering at the boundaries. In contrast to recent studies of an adiabatic ideal gas with a piston [R.C. Lua and A.Y. Grosberg, J. Phys. Chem. B 109, 6805 (2005); I. Bena, Europhys. Lett. 71, 879 (2005)], the container and piston stay in contact with the heat bath during the work process. Under this condition the heat reservoir as well as the system depend on the work parameter lambda and microscopic reversibility is broken for a moving piston. Our model is thus not included in the class of systems for which the nonequilibrium work theorem has been derived rigorously either by Hamiltonian [C. Jarzynski, J. Stat. Mech. (2004) P09005] or stochastic methods [G.E. Crooks, J. Stat. Phys. 90, 1481 (1998)]. Nevertheless the validity of the nonequilibrium work theorem is confirmed both numerically for a wide range of parameter values and analytically in the limit of a very fast moving piston, i.e., in the far nonequilibrium regime.
A strongly coupled open system with a non-linear bath: fluctuation-dissipation and Langevin dynamics
Bhadra, Chitrak
2018-03-01
The study of Langevin dynamics and fluctuation-dissipation relation (FDR) for a generic probe system (represented by a mass M ), bilinearly coupled to a bath of harmonic oscillators, has been a standard paradigm for the microscopic theory of stochastic processes for several decades. The question that we probe in this paper is, how robust the structure of the classical FDR is, when one replaces the harmonic bath by an anharmonic one in the limit of strong system-bath coupling? Such a picture carries the signature of the probe system in the zeroth order through a nonlocal time kernel. We observe that the two-time noise correlations hold a rich structure from which the usual FDR emerges only in the leading order of perturbation. Beyond this order, multiple time scales and nontrivial dependence on the temperature starts to manifest. These new aspects conspire to break the time-translational invariance of the noise-correlations. Several other interesting features show up and we discuss them methodically through rigorous calculations order-by-order in perturbation. This formalistic derivation along with a specific example of non-linearity can be easily applied to a huge range of processes and statistical observables that fall under the purview of a system-reservoir theory.
Molecular quantum magnetism with strong spin-orbit coupling in inorganic solid Ba3Yb2Zn5O11
Park, Sang-Youn; Ji, Sungdae; Park, Jae-Hoon; Do, Seunghwan; Choi, Kwang-Yong; Jang, Dongjin; Schmidt, Burkhard; Brando, Manuel; Butch, Nicholas
The molecular magnet, assembly of finite number of spins which are isolated from environment, is a model system to study the quantum information process such as the qubit or spintronic devices. In past decades, the molecular magnet has been mostly realized in organic material, however, it has difficulty synthesizing materials or controlling their properties, meanwhile tremendous endeavors to search inorganic molecular magnet are continuing. Here, we propose Ba3Yb2Zn5O11 as a candidate of inorganic molecular magnet. This material consists of an alternating 3D-array of small and large tetrahedron containing antiferromagnetically coupled four pseudospin-1/2 Yb ions, and magnetic properties are described by an isolated tetrahedron without long-range magnetic ordering. Inelastic neutron scattering measurement with external magnetic field reveals that extraordinarily huge Dzyaloshinsky-Moriya (DM) interaction originating from strong spin-orbit coupling in Yb isospin is the key to explain energy level of tetrahedron in addition to Heisenberg exchange interaction and Zeeman effect. Magnetization measurement shows the Landau-Zener transition between avoided crossing levels caused by DM interaction.
NEON's Eddy-Covariance Storage Exchange: from Tower to Data Portal
Durden, N. P.; Luo, H.; Xu, K.; Metzger, S.; Durden, D.
2017-12-01
NEON's eddy-covariance storage exchange system (ECSE) consists of a suite of sensors including temperature sensors, a CO2 and H2O gas analyzer, and isotopic CO2 and H2O analyzers. NEON's ECSE was developed to provide the vertical profile measurements of temperature, CO2 and H2O concentrations, the stable isotope ratios in CO2 (δ13C) and H2O (δ18O and δ2H) in the atmosphere. The profiles of temperature and concentrations of CO2 and H2O are key to calculate storage fluxes for eddy-covariance tower sites. Storage fluxes have a strong diurnal cycle and can be large in magnitude, especially at temporal scales less than one day. However, the storage term is often neglected in flux computations. To obtian accurate eddy-covariance fluxes, the storage fluxes are calculated and incorporated into the calculations of net surface-atmosphere ecosystem exchange of heat, CO2, and H2O for each NEON tower site. Once the ECSE raw data (Level 0, or L0) is retrieved at NEON's headquarters, it is preconditioned through a sequence of unit conversion, time regularization, and plausibility tests. By utilizing NEON's eddy4R framework (Metzger et al., 2017), higher-level data products are generated including: Level 1 (L1): Measurement-level specific averages of temperature and concentrations of CO2 and H2O. Level 2 (L2): Time rate of change of temperature and concentrations of CO2 and H2O over 30 min at each measurement level along the vertical tower profile. Level 3 (L3): Time rate of change of temperature and concentrations of CO2 and H2O over 30 min (L2), spatially interpolated along the vertical tower profile. Level 4 (L4): Storage fluxes of heat, CO2, and H2O calculated from the integrated time rate of change spatially interpolated profile (L3). The L4 storage fluxes are combined with turbulent fluxes to calculate the net surface-atmosphere ecosystem exchange of heat, CO2, and H2O. Moreover, a final quality flag and uncertainty budget are produced individually for each data stream
Investigations of Townsend discharges in neon by mass spectrometry
International Nuclear Information System (INIS)
Dielis, J.W.H.
1979-01-01
The decay frequency of Ne( 3 P 2 )-atoms has been determined at 77 K and 295 K as a function of gas density from time sampling analysis of a N + 2 -ion impurity in the afterglow of a Townsend discharge in neon. From the sampling spectra of ions in the afterglow of a Townsend discharge, mobilities of positive ions in neon have been determined as a function of the reduced electric field strength at 77 K and 295 K. From mobility data the interaction potential as a function of intermolecular distance between a N + 2 -ion and a neon atom is evaluated. (Auth.)
Gupta, Akanksha; Ganesh, Rajaraman; Joy, Ashwin
2018-01-01
In this paper, we perform comparative studies of compressible Kolmogorov flow in the two-dimensional strongly coupled dusty plasma by means of atomistic or molecular dynamics (MD) and continuum or computational fluid dynamics (CFD) methods. Recently, using MD simulation, generation of molecular shear heat at the atomistic level is shown to reduce the average coupling strength of the system and destruct the vortical structures. To suppress the molecular heat, a novel method of a thermostat, namely, the configurational thermostat is introduced by which the microscale heat generated by the shear flow has shown to be thermostatted out efficiently without compromising the large scale vortex dynamics. While using a configurational thermostat, it has been found that the growth rate obtained from both the studies is the same with the marginal difference. To make the comparison with the continuum fluid model, we perform the same study using the generalised hydrodynamic model, wherein molecular shear heating phenomena is completely absent, however, viscous dissipation is there at the macroscale level. For this purpose, an Advanced Generalised SPECTral Code has been developed to study the linear and nonlinear aspects of the Kolmogorov flow in the incompressible and compressible limit for viscoelastic fluids. All the phenomenological parameters used in CFD simulations have been calculated from MD simulations. Code is benchmarked against the eigen value solver in the linear regime. Linear growth-rates calculated from the phenomenological fluid model is found to be close to that obtained from MD simulation for the same set of input parameters. The transition from laminar to turbulent flow has been found at a critical value of Reynolds number Rc in both the macroscopic (CFD) and microscopic (MD) simulation. Rc in MD is smaller than the one obtained by CFD simulation. In the nonlinear regime of CFD, the mode becomes unstable and vortex formation happens earlier than in MD. The
Current sheath curvature correlation with the neon soft x-ray emission from plasma focus device
International Nuclear Information System (INIS)
Zhang, T; Lin, X; Chandra, K A; Tan, T L; Springham, S V; Patran, A; Lee, P; Lee, S; Rawat, R S
2005-01-01
The insulator sleeve length is one of the major parameters that can severely affect the neon soft x-ray yield from a plasma focus. The effect of the insulation sleeve length on various characteristic timings of plasma focus discharges and hence the soft x-ray emission characteristics has been investigated using a resistive divider. The pinhole images and laser shadowgraphy are used to explain the observed variation in the average soft x-ray yield (measured using a diode x-ray spectrometer) with variation of the insulator sleeve length. We have found that for a neon filled plasma focus device the change in insulator sleeve length changes the current sheath curvature angle and thus the length of the focused plasma column. The optimized current sheath curvature angle is found to be between 39 0 and 41 0 , at the specific axial position of 6.2-9.3 cm from the cathode support plate, for our 3.3 kJ plasma focus device. A strong dependence of the neon soft x-ray yield on the current sheath curvature angle has thus been reported
Energy Technology Data Exchange (ETDEWEB)
Capecelatro, Jesse, E-mail: jcaps@illinois.edu [Coordinated Science Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801-2307 (United States); Desjardins, Olivier [Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853 (United States); Fox, Rodney O. [Department of Chemical and Biological Engineering, Center for Multiphase Flow Research, Iowa State University, Ames, Iowa 50011-2230 (United States); Laboratoire EM2C, CNRS, CentraleSupélec, Université Paris-Saclay, Grande Vois des Vignes, 92295 Chatenay Malabry (France)
2016-03-15
Simulations of strongly coupled (i.e., high-mass-loading) fluid-particle flows in vertical channels are performed with the purpose of understanding the fundamental physics of wall-bounded multiphase turbulence. The exact Reynolds-averaged (RA) equations for high-mass-loading suspensions are presented, and the unclosed terms that are retained in the context of fully developed channel flow are evaluated in an Eulerian–Lagrangian (EL) framework for the first time. A key distinction between the RA formulation presented in the current work and previous derivations of multiphase turbulence models is the partitioning of the particle velocity fluctuations into spatially correlated and uncorrelated components, used to define the components of the particle-phase turbulent kinetic energy (TKE) and granular temperature, respectively. The adaptive spatial filtering technique developed in our previous work for homogeneous flows [J. Capecelatro, O. Desjardins, and R. O. Fox, “Numerical study of collisional particle dynamics in cluster-induced turbulence,” J. Fluid Mech. 747, R2 (2014)] is shown to accurately partition the particle velocity fluctuations at all distances from the wall. Strong segregation in the components of granular energy is observed, with the largest values of particle-phase TKE associated with clusters falling near the channel wall, while maximum granular temperature is observed at the center of the channel. The anisotropy of the Reynolds stresses both near the wall and far away is found to be a crucial component for understanding the distribution of the particle-phase volume fraction. In Part II of this paper, results from the EL simulations are used to validate a multiphase Reynolds-stress turbulence model that correctly predicts the wall-normal distribution of the two-phase turbulence statistics.
Sato, T; Tanaka, Y; Nakayama, K; Souma, S; Takahashi, T; Sasaki, S; Ren, Z; Taskin, A A; Segawa, Kouji; Ando, Yoichi
2013-05-17
We have performed angle-resolved photoemission spectroscopy on the strongly spin-orbit coupled low-carrier density superconductor Sn(1-x)In(x)Te (x = 0.045) to elucidate the electronic states relevant to the possible occurrence of topological superconductivity, as recently reported for this compound based on point-contact spectroscopy. The obtained energy-band structure reveals a small holelike Fermi surface centered at the L point of the bulk Brillouin zone, together with a signature of a topological surface state, indicating that this material is a doped topological crystalline insulator characterized by band inversion and mirror symmetry. A comparison of the electronic states with a band-noninverted superconductor possessing a similar Fermi surface structure, Pb(1-x)Tl(x)Te, suggests that the anomalous behavior in the superconducting state of Sn(1-x)In(x)Te is related to the peculiar orbital characteristics of the bulk valence band and/or the presence of a topological surface state.
Measurement of the strong interaction coupling constant αs by jet study in the H1 experiment
International Nuclear Information System (INIS)
Squinabol, F.
1997-01-01
The H1 experiment allows to study hadronic jets produced in deep inelastic lepton (27.5 GeV) scattering off protons (820 GeV). The coupling constant of the strong interaction α s can be extracted from the measurement of the 2-jets rate in the final state. The use of the JADE algorithm is optimal for events with high energy transfer (100-4,000 GeV 2 ), corresponding to the 1994 and 1995 data. The error on α s (M Z 0 2 ) is dominated by the uncertainty from the hadronic energy measurement and the experimental resolution effects on jets. The theoretical error is dominated by the renormalization scale dependence. The final result is (M Z 0 2 ) 0.118 -0.008 +0.008 . This analysis is extended to smaller momentum transfers (25-100 GeV 2 ) using the factorizable K t algorithm, taking the transferred momentum as energy scale of the particle re-clustering. The result α s (M Z 0 2 ) 0.117 -0.008 +0.009 is compatible with the previous one. The precision of the measurement performed in this thesis is 7%. A precision of 4% could be achieved after progresses in the theoretical framework and/or after a significant increase of the luminosity. (author)
Gangolf, Thomas; Blecher, Marius; Bolanos, Simon; Lancia, Livia; Marques, Jean-Raphael; Cerchez, Mirela; Prasad, Rajendra; Aurand, Bastian; Loiseau, Pascal; Fuchs, Julien; Willi, Oswald
2017-10-01
In the ongoing quest for novel techniques to obtain ever higher laser powers, plasma amplification has drawn much attention, benefiting from the fact that a plasma can sustain much higher energy densities than a solid state amplifier. As a plasma process, Stimulated Brillouin Backscattering in the strong coupling regime (sc-SBS) can be used to transfer energy from one laser pulse (pump) to another (seed), by a nonlinear ion oscillation forced by the pump laser. Here, we report on experimental results on amplification by sc-SBS using the ARCTURUS Ti:Sapphire multi-beam laser system at the University of Duesseldorf, Germany. Counter-propagating in a supersonic Hydrogen gas jet target, an ultrashort seed pulse with a pulse duration between 30 and 160 fs and an energy between 1 and 12 mJ was amplified by a high-energy pump pulse (1.7 ps, 700 mJ). For some of the measurements, the gas was pre-ionized with a separate laser pulse (780 fs, 460 mJ). Preliminary analysis shows that the amplification was larger for the longer seed pulses, consistent with theoretical predictions.
Tahir, N A; Shutov, A; Udrea, S; Deutsch, C; Fortov, V E; Gryaznov, V; Hoffmann, Dieter H H; Jacobi, J; Kain, V; Kuster, M; Ni, P; Piriz, A R; Schmidt, R; Spiller, P; Varentsov, D; Zioutas, K
2006-01-01
Detailed theoretical studies have shown that intense heavy-ion beams that will be generated at the future Facility for Antiprotons and Ion Research (FAIR) (Henning 2004 Nucl. Instrum. Methods B 214 211) at Darmstadt will be a very efficient tool to create high-energy-density (HED) states in matter including strongly coupled plasmas. In this paper we show, with the help of two-dimensional numerical simulations, the interesting physical states that can be achieved considering different beam intensities using zinc as a test material. Another very interesting experiment that can be performed using the intense heavy-ion beam at FAIR will be generation of low-entropy compression of a test material such as hydrogen that is enclosed in a cylindrical shell of a high-Z material such as lead or gold. In such an experiment, one can study the problem of hydrogen metallization and the interiors of giant planets. Moreover, we discuss an interesting method to diagnose the HED matter that is at the centre of the Sun. We have ...
Energy Technology Data Exchange (ETDEWEB)
Tahir, N A [Gesellschaft fuer Schwerionenforschung, 64291 Darmstadt (Germany); Lomonosov, I V [Institute for Problems of Chemical Physics Research, Chernogolovka (Russian Federation); Shutov, A [Institute for Problems of Chemical Physics Research, Chernogolovka (Russian Federation); Udrea, S [Institut fuer Kernphysik, TU Darmstadt, 64289 Darmstadt (Germany); Deutsch, C [LPGP, Universite Paris-Sud, 91405 Orsay (France); Fortov, V E [Institute for Problems of Chemical Physics Research, Chernogolovka (Russian Federation); Gryaznov, V [Institute for Problems of Chemical Physics Research, Chernogolovka (Russian Federation); Hoffmann, D H H [Gesellschaft fuer Schwerionenforschung, 64291 Darmstadt (Germany); Jacobi, J [Institut fuer Angewandte Physik, Universitaet Frankfurt, 60438 Frankfurt (Germany); Kain, V [CERN, 1211 Geneva (Switzerland); Kuster, M [Institut fuer Kernphysik, TU Darmstadt, 64289 Darmstadt (Germany); Ni, P [Institut fuer Kernphysik, TU Darmstadt, 64289 Darmstadt (Germany); Piriz, A R [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Schmidt, R [CERN, 1211 Geneva (Switzerland); Spiller, P [Gesellschaft fuer Schwerionenforschung, 64291 Darmstadt (Germany); Varentsov, D [Institut fuer Kernphysik, TU Darmstadt, 64289 Darmstadt (Germany); Zioutas, K [CERN, 1211 Geneva (Switzerland)
2006-04-28
Detailed theoretical studies have shown that intense heavy-ion beams that will be generated at the future Facility for Antiprotons and Ion Research (FAIR) (Henning 2004 Nucl. Instrum. Methods B 214 211) at Darmstadt will be a very efficient tool to create high-energy-density (HED) states in matter including strongly coupled plasmas. In this paper we show, with the help of two-dimensional numerical simulations, the interesting physical states that can be achieved considering different beam intensities using zinc as a test material. Another very interesting experiment that can be performed using the intense heavy-ion beam at FAIR will be generation of low-entropy compression of a test material such as hydrogen that is enclosed in a cylindrical shell of a high-Z material such as lead or gold. In such an experiment, one can study the problem of hydrogen metallization and the interiors of giant planets. Moreover, we discuss an interesting method to diagnose the HED matter that is at the centre of the Sun. We have also carried out simulations to study the damage caused by the full impact of the Large Hadron Collider (LHC) beam on a superconducting magnet. An interesting outcome of this study is that the LHC beam can induce HED states in matter.
Li, Meng; Gu, Xian-Ming; Huang, Chengming; Fei, Mingfa; Zhang, Guoyu
2018-04-01
In this paper, a fast linearized conservative finite element method is studied for solving the strongly coupled nonlinear fractional Schrödinger equations. We prove that the scheme preserves both the mass and energy, which are defined by virtue of some recursion relationships. Using the Sobolev inequalities and then employing the mathematical induction, the discrete scheme is proved to be unconditionally convergent in the sense of L2-norm and H α / 2-norm, which means that there are no any constraints on the grid ratios. Then, the prior bound of the discrete solution in L2-norm and L∞-norm are also obtained. Moreover, we propose an iterative algorithm, by which the coefficient matrix is independent of the time level, and thus it leads to Toeplitz-like linear systems that can be efficiently solved by Krylov subspace solvers with circulant preconditioners. This method can reduce the memory requirement of the proposed linearized finite element scheme from O (M2) to O (M) and the computational complexity from O (M3) to O (Mlog M) in each iterative step, where M is the number of grid nodes. Finally, numerical results are carried out to verify the correction of the theoretical analysis, simulate the collision of two solitary waves, and show the utility of the fast numerical solution techniques.
Ghosh, Samiran
2014-09-01
The propagation of a nonlinear low-frequency mode in two-dimensional (2D) monolayer hexagonal dusty plasma crystal in presence of external magnetic field and dust-neutral collision is investigated. The standard perturbative approach leads to a 2D Korteweg-de Vries (KdV) soliton for the well-known dust-lattice mode. However, the Coriolis force due to crystal rotation and Lorentz force due to magnetic field on dust particles introduce a linear forcing term, whereas dust-neutral drag introduce the usual damping term in the 2D KdV equation. This new nonlinear equation is solved both analytically and numerically to show the competition between the linear forcing and damping in the formation of quasilongitudinal soliton in a 2D strongly coupled complex (dusty) plasma. Numerical simulation on the basis of the typical experimental plasma parameters and the analytical solution reveal that the neutral drag force is responsible for the usual exponential decay of the soliton, whereas Coriolis and/or Lorentz force is responsible for the algebraic decay as well as the oscillating tail formation of the soliton. The results are discussed in the context of the plasma crystal experiment.
Gupta, Akanksha; Ganesh, Rajaraman
2018-01-01
We study compressibility effects on the two-dimensional strongly coupled dusty plasma by means of computational fluid dynamics (CFD) with the Kolmogorov flow as an initial shear flow profile. Nonlinear compressible vortex flow dynamics and other linear and nonlinear properties of such flow in the presence of variable density, pressure, and electrostatic potential are addressed using a generalised compressible hydrodynamic model. The stabilizing effect of compressibility on the unstable shear flows in the presence of strong correlation ( τm>0 ) is presented. Increasing the Mach number relatively reduces the growth-rate of perturbation. On the other hand, strong correlation makes the medium to be more unstable and increases the growth rate. Using an eigen value solver, various linear properties of compressible Kolmogorov flow have been investigated for a range of variable parameters, for example, Mach number, Reynolds number, and viscoelastic coefficient (τm). Compressible Kolmogorov flow becomes unstable above a critical value of the Reynolds number (Rc), and below Rc, the shear flow is found to be neutrally stable. In this study, it is found that the viscoelasticity reduces the value of Rc. For our choice of parameters, at τm=τmc , the compressible Kolmogorov flow becomes unconditionally unstable and no Rc exists for values of τm higher than τmc . To address the nonlinear properties, for example, mode-mode interaction due to the presence of nonlinearity in the fluid, vortex formation, etc., a massively parallelized Advanced Generalized SPECTral Code (AG-Spect) has been developed. AG-Spect, a newly developed code, is an efficient tool to solve any set of nonlinear fluid dynamic equations. A good agreement in linear growth rates obtained from the eigen value solver and time dependent simulation (AG-Spect) is found. In our CFD study, the suppression of instability, elongated vortex structures, pattern formation, nonlinear saturation, and visco
Collisional interaction between metastable neon atoms
Energy Technology Data Exchange (ETDEWEB)
Drunen, Wouter Johannes van
2008-07-07
In this thesis, the study of cold gases of neon atoms in different metastable states is described. It contains measurements of the collisional parameters for both the 3s[3/2]{sub 2} and the 3s'[1/2]{sub 0} metastable state and the dependence of the inelastic loss on external fields. Furthermore, the investigation of frequency dependent laser-induced collisions, and the possibility to excite photoassociation resonances is presented. For the measurements described here, neon atoms have been confined in a magnetooptical trap, in a magnetostatic trap, or in an optical dipole trap, respectively. By laser cooling inside the magnetic trap, atomic samples with more than 95 percent occupation of the magnetic substate m{sub J} = +2 could be prepared. They have a typical temperature of 0.5 mK, central densities up to 10{sup 11} cm{sup -3}, and a central phase-space density of up to 2.2.10{sup -7}. After loading the optical dipole trap from the magnetic trap, 2.5.10{sup 6} atoms with typical temperatures of 0.1 mK, and central densities up to 5.10{sup 10} cm{sup -3} were trapped. By evaporative cooling of the atoms in the magnetic trap we could increase the phase-space density by a factor of 200 to 5.10{sup -5}. Investigating the frequency dependence of laser-induced collisions did not reveal an experimental signature for the excitation of photoassociation resonances. For the {sup 3}D{sub 3} line a frequency dependence of laser enhanced Penning ionization was observed. Measurement of the two-body loss coefficient as function of the magnetic field showed a field dependence of the inelastic loss. These losses increase towards both small and large offset fields. The implementation of an optical dipole trap allowed us to trap the {sup 3}P{sub 0} metastable state. From the trap loss measurements we determined the two-body loss coefficient of the {sup 3}P{sub 0} metastable state for both bosonic isotopes {sup 20}Ne and {sup 22}Ne. For {sup 20}Ne we obtained {beta}=6{sup +5}{sub
Laying the groundwork for NEON's continental-scale ecological research
Dethloff, G.; Denslow, M.
2013-12-01
The National Ecological Observatory Network (NEON) is designed to examine a suite of ecological issues. Field-collected data from 96 terrestrial and aquatic sites across the U.S. will be combined with remotely sensed data and existing continental-scale data sets. Field collections will include a range of physical and biological types, including soil, sediment, surface water, groundwater, precipitation, plants, animals, insects, and microbes as well as biological sub-samples such as leaf material, blood and tissue samples, and DNA extracts. Initial data analyses and identifications of approximately 175,000 samples per year will occur at numerous external laboratories when all sites are fully staffed in 2017. Additionally, NEON will archive biotic and abiotic specimens at collections facilities where they will be curated and available for additional analyses by the scientific community. The number of archived specimens is currently estimated to exceed 130,000 per year by 2017. We will detail how NEON is addressing the complexities and challenges around this set of analyses and specimens and how the resulting high-quality data can impact ecological understanding. The raw data returned from external laboratories that is quality checked and served by NEON will be the foundation for many NEON data products. For example, sequence-quality nucleic acids extracted from surface waters, benthic biofilms, and soil samples will be building blocks for data products on microbial diversity. The raw sequence data will also be available for uses such as evolutionary investigations, and the extracts will be archived so others can acquire them for additional research. Currently, NEON is establishing contracts for the analysis and archiving of field-collected samples through 2017. During this period, NEON will gather information on the progress and success of this large-scale effort in order to determine the most effective course to pursue with external facilities. Two areas that NEON
Investigations on afterglows of neon gas discharges
International Nuclear Information System (INIS)
Steenhuysen, L.W.G.
1979-01-01
Experimental and numerical investigations on afterglows of neon gas discharges are described. The investigated pressure range extends from 0.5 torr to 100 torr; the discharge currents lie between about 1 mA and 100 mA. The decay of the 1s atom densities has been determined experimentally as function of the time elapsed in the afterglow. From the measured decay of metastable 1s 5 atom densities at gas pressure 5 atoms as well as the coefficinets of atomic collisional transfer between the 1s 5 and 1s 4 level are determined. To obtain more insight in the mutual influences of the various loss and production processes of 1s atoms and charge carriers in the afterglow a numerical model has been formed. The behaviour of the afterglow radiation intensity has been measured on discharges with a gas pressure of 1, 10, 20, 50 and 100 torr and a discharge current of 22, 24 and 50 mA. From the results the recombination distribution fractions of the 1s levels are determined and the electron densities at the start of the afterglow of 20, 50 and 100 torr discharges. With the help of the selective excitation spectroscopy the coefficients of atomic transfer between the 2p levels have been measured in the afterglow of discharge with a gas pressure of 1, 10, 20, 50 and 100 torr and a discharge current of 22 mA. From these results and the measured intensities of the various spectral lines in the afterglow the partial recombination coefficients for the 2p levels are calculated. (Auth. )
Energy Technology Data Exchange (ETDEWEB)
Devoret, M.H. [College de France, 75231 Paris cedex 05 (France); Girvin, Steven; Schoelkopf, Robert [Applied Physics Department, Yale University, New Haven, CT 06520-8284 (United States)
2007-10-15
After reviewing the limitation by the fine structure constant {alpha} of the dimensionless coupling constant of an hydrogenic atom with a mode of the electromagnetic field in a cavity, we show that the situation presents itself differently for an artificial Josephson atom coupled to a transmission line resonator. Whereas the coupling constant for the case where such an atom is placed inside the dielectric of the resonator is proportional to {alpha}{sup 1/2}, the coupling of the Josephson atom when it is placed in series with the conducting elements of the resonator is proportional to {alpha}{sup -1/2} and can reach values greater than 1. (Abstract Copyright [2007], Wiley Periodicals, Inc.)
International Nuclear Information System (INIS)
Achterberg, O.; D'Agostini, G.; Apel, W.D.; Engler, J.; Fluegge, G.; Forstbauer, B.; Fries, D.C.; Fues, W.; Gamerdinger, K.; Henkes, T.; Hopp, G.; Krueger, M.; Kuester, H.; Mueller, H.; Randoll, H.; Schmidt, G.; Schneider, H.; Boer, W. de; Buschhorn, G.; Grindhammer, G.; Grosse-Wiesmann, P.; Gunderson, B.; Kiesling, C.; Kotthaus, R.; Kruse, U.; Lierl, H.; Lueers, D.; Oberlack, H.; Schacht, P.; Bonneaud, G.; Colas, P.; Cordier, A.; Davier, M.; Fournier, D.; Grivaz, J.F.; Haissinski, J.; Journe, V.; Laplanche, F.; Le Diberder, F.; Mallik, U.; Ros, E.; Veillet, J.J.; Behrend, H.J.; Fenner, H.; Schachter, M.J.; Schroeder, V.; Sindt, H.
1983-12-01
Hadronic events obtained with the CELLO detector at PETRA are compared with second order QCD predictions using different models for the fragmentation of quarks and gluons into hadrons. We find that the model dependence in the determination of the strong coupling constant persists when going from first to second order QCD calculations. (orig.)
Gaaloul, Sana; Delinchant, Benoît; Wurtz, Frédéric; Thiers, Stéphane; Peuportier, Bruno
2011-01-01
International audience; The context of this study is the coupling of thermal and electrical models in order to efficiently simulate energy consumption in buildings, which requires managing interoperability problems between simulation environments. The coupling is accomplished in MATLAB™ tool between a thermal model of a building envelope using COMFIE software and an electrical heater model. Our purpose is to study and generalize the interoperability between these two domains governed by pheno...
Takigawa, N.; Michel, F.; Balantekin, A. B.; Reidemeister, G.
1991-06-01
We offer a novel interpretation of the deviation of the experimental angular distribution for elastic 18O+ 184W scattering at 90 MeV from the standard Fresnel diffraction pattern in terms of an interference between scattering amplitudes corresponding to different orientations of the target nucleus. The importance of Coriolis coupling, which is initially neglected in this geometric approach, is discussed in the case where long-range Coulomb coupling is active.
Energy Technology Data Exchange (ETDEWEB)
Takigawa, N. (Tohoku Univ., Sendai (Japan). Dept. of Physics); Michel, F. (Mons Univ. (Belgium). Faculte des Sciences); Balantekin, A.B. (Wisconsin Univ., Madison (USA). Dept. of Physics); Reidemeister, G. (Universite Libre de Bruxelles (Belgium). Faculte des Sciences)
1991-06-20
We offer a novel interpretation of the deviation of the experimental angular distribution for elastic {sup 18}O+{sup 184}W scattering at 90 MeV from the standard Fresnel diffraction pattern in terms of an interference between scattering amplitudes corresponding to different orientations of the target nucleus. The importance of Coriolis coupling, which is initially neglected in this geometric approach, is discussed in the case where long-range Coulomb coupling is active. (orig.).
International Nuclear Information System (INIS)
Astruc, J.M.
1967-12-01
In the first part, free-convection and nucleate pool boiling heat transfer (up to burn-out heat flux) between a platinum wire of 0.15 mm in diameter in neon, deuterium and hydrogen has been studied at atmospheric pressure. These measurements were continued in liquid neon up to 23 bars (Pc ≅ 26.8 b). Film boiling heat transfer coefficients have been measured in pool boiling liquid neon at atmospheric pressure with three heating wires (diameters 0.2, 0.5, 2 mm). All the results have been compared with existing correlations. The second part is devoted to measurements of the critical heat flux limiting heat transfer with small temperature differences between the wall and the liquid neon flowing inside a tube (diameters 3 x 3.5 mm) heated by joule effect on 30 cm of length. Influences of flow stability, nature of electrical current, pressure, mass flow rate and subcooling are shown. In conclusion, the similarity of the heat transfer characteristics in pool boiling as well as in forced convection of liquid neon and hydrogen is emphasized. (author) [fr
NEON INSIGHTS FROM OLD SOLAR X-RAYS: A PLASMA TEMPERATURE DEPENDENCE OF THE CORONAL NEON CONTENT
International Nuclear Information System (INIS)
Drake, Jeremy J.
2011-01-01
An analysis using modern atomic data of fluxes culled from the literature for O VIII and Ne IX lines observed in solar active regions by the P78 and Solar Maximum Mission satellites confirms that the coronal Ne/O abundance ratio varies by a factor of two or more, and finds an increase in Ne/O with increasing active region plasma temperature. The latter is reminiscent of evidence for increasing Ne/O with stellar activity in low-activity coronae that reaches a 'neon saturation' in moderately active stars at approximately twice the historically accepted solar value of about 0.15 by number. We argue that neon saturation represents the underlying stellar photospheric compositions, and that low-activity coronae, including that of the Sun, are generally depleted in neon. The implication would be that the solar Ne/O abundance ratio should be revised upward by a factor of about two to n(Ne)/n(O) ∼ 0.3. Diverse observations of neon in the local cosmos provide some support for such a revision. Neon would still be of some relevance for reconciling helioseismology with solar models computed using recently advocated chemical mixtures with lower metal content.
Neon adsorption on oxidized single-walled carbon nanohorns
Krungleviciute, Vaiva; Migone, Aldo; Yudasaka, Masako; Iijima, Sumio
2012-02-01
We will present the results of a study of neon adsorption on oxidized single-walled carbon nanohorns. Our adsorption isotherm measurements were conducted at temperatures below 24.5 K, the triple point for Ne. Results for the effective specific surface area and for the effective pore volume of the nanohorn aggregates will be presented. We will also report on the sorbent-loading dependence of the isosteric heat of neon on the nanohorns, and on the binding energy. Our results for this system will be compared with those obtained for Ne on a sample of dahlia-like nanohorns annealed at 520 K.
Dew Frequency across the NEON Network from Infrared Radiometry
Ritter, F.; Berkelhammer, M. B.; Beysens, D.
2017-12-01
The surface energy budget is more difficult to close at night because of the absence of strong atmospheric turbulence, central in the eddy-covariance calculations. One approach to assessing the direction of the nocturnal latent heat flux is through studying the frequency and magnitude of dew formation in different ecosystems. However, most former dew studies on dew dynamics utilized artificial surfaces to collect dew, and did not have access to the surface temperature of natural surfaces in an ecosystem to provide a continuous whole-plot approach to constrain dew formation. Hourly in-situ measurements recently made available by the National Ecological Observatory Network (NEON) of the radiometric surface temperature and the meteorological variables provide a unique opportunity to make continuous estimates of dew formation across 19 ecosystems (9 grasslands and 10 forests) at the plot-scale. Here, dew duration was calculated for each night based on the difference between the surface temperature and the dew point temperature of the air. The results from this analysis show that dew duration is limited by wind speed during the night, with a maximum dew yield at 1.1 m/s and no dew occurrence when the wind speed exceeds 7 m/s. This observation is consistent with previous studies but has been expanded here across multiple biomes to produce a well-defined turbulent limit on dew formation. The sensitivity of dew to wind speed arises because of the exhaustion of the water vapor supply close to the surface of the leaf at very low wind speed, and because the enhanced thermal exchange between the air and the surface counteracts dewfall at high wind speed. This well-defined wind speed limit that persists across sites and seasons could help to estimate the surface energy budget at night by constraining the latent heat flux.
Continuum strong-coupling expansion of Yang-Mills theory: quark confinement and infra-red slavery
Energy Technology Data Exchange (ETDEWEB)
Mansfield, P. (Dept. of Mathematical Sciences, Univ. of Durham (United Kingdom))
1994-04-25
We solve Schroedinger's equation for the ground-state of four-dimensional Yang-Mills theory as an expansion in inverse powers of the coupling. Expectation values computed with the leading-order approximation are reduced to a calculation in two-dimensional Yang-Mills theory which is known to confine. Consequently the Wilson loop in the four-dimensional theory obeys an area law to leading order and the coupling becomes infinite as the mass scale goes to zero. (orig.)
Continuum strong-coupling expansion of Yang-Mills theory: quark confinement and infra-red slavery
Mansfield, Paul
1994-04-01
We solve Schrödinger's equation for the ground-state of four-dimensional Yang-Mills theory as an expansion in inverse powers of the coupling. Expectation values computed with the leading-order approximation are reduced to a calculation in two-dimensional Yang-Mills theory which is known to confine. Consequently the Wilson loop in the four-dimensional theory obeys an area law to leading order and the coupling becomes infinite as the mass scale goes to zero.
Casalderrey-Solana, Jorge; Milhano, José Guilherme; Pablos, Daniel; Rajagopal, Krishna
2016-01-01
We have previously introduced a hybrid strong/weak coupling model for jet quenching in heavy ion collisions that describes the production and fragmentation of jets at weak coupling, using PYTHIA, and describes the rate at which each parton in the jet shower loses energy as it propagates through the strongly coupled plasma, dE/dx, using an expression computed holographically at strong coupling. The model has a single free parameter that we fit to a single experimental measurement. We then confront our model with experimental data on many other jet observables, focusing here on boson-jet observables, finding that it provides a good description of present jet data. Next, we provide the predictions of our hybrid model for many measurements to come, including those for inclusive jet, dijet, photon-jet and Z-jet observables in heavy ion collisions with energy $\\sqrt{s}=5.02$ ATeV coming soon at the LHC. As the statistical uncertainties on near-future measurements of photon-jet observables are expected to be much sm...
Optimization of mNeonGreen for Homo sapiens increases its fluorescent intensity in mammalian cells.
Tanida-Miyake, Emiko; Koike, Masato; Uchiyama, Yasuo; Tanida, Isei
2018-01-01
Green fluorescent protein (GFP) is tremendously useful for investigating many cellular and intracellular events. The monomeric GFP mNeonGreen is about 3- to 5-times brighter than GFP and monomeric enhanced GFP and shows high photostability. The maturation half-time of mNeonGreen is about 3-fold faster than that of monomeric enhanced GFP. However, the cDNA sequence encoding mNeonGreen contains some codons that are rarely used in Homo sapiens. For better expression of mNeonGreen in human cells, we synthesized a human-optimized cDNA encoding mNeonGreen and generated an expression plasmid for humanized mNeonGreen under the control of the cytomegalovirus promoter. The resultant plasmid was introduced into HEK293 cells. The fluorescent intensity of humanized mNeonGreen was about 1.4-fold higher than that of the original mNeonGreen. The humanized mNeonGreen with a mitochondria-targeting signal showed mitochondrial distribution of mNeonGreen. We further generated an expression vector of humanized mNeonGreen with 3xFLAG tags at its carboxyl terminus as these tags are useful for immunological analyses. The 3xFLAG-tagged mNeonGreen was recognized well with an anti-FLAG-M2 antibody. These plasmids for the expression of humanized mNeonGreen and mNeonGreen-3xFLAG are useful tools for biological studies in mammalian cells using mNeonGreen.
Pickup and Photodissociation of Hydrogen Halides in Floppy Neon Clusters
Czech Academy of Sciences Publication Activity Database
Slavíček, Petr; Jungwirth, Pavel; Lewerenz, M.; Nahler, N. H.; Fárnik, M.; Buck, U.
2003-01-01
Roč. 107, - (2003), s. 7743-7754 ISSN 1089-5639 R&D Projects: GA MŠk LN00A032 Institutional research plan: CEZ:AV0Z4040901 Keywords : photodissociation * neon clusters Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.792, year: 2003
21 CFR 868.1670 - Neon gas analyzer.
2010-04-01
... patient. The device may use techniques such as mass spectrometry or thermal conductivity. (b... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Neon gas analyzer. 868.1670 Section 868.1670 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL...
Helium Neon laser therapy for post mastectomy lymphedema and ...
African Journals Online (AJOL)
The aim of this work was to evaluate the efficacy of Helium Neon (He–Ne) laser therapy on post mastectomy lymphedema and shoulder mobility. Thirty female patients with axillary lymph node dissection (ALND), with or without radiotherapy had been participated in this study. The patients were randomly divided into two ...
Molecular Iodine Fluorescence Using a Green Helium-Neon Laser
Williamson, J. Charles
2011-01-01
Excitation of molecular iodine vapor with a green (543.4 nm) helium-neon laser produces a fluorescence spectrum that is well suited for the upper-level undergraduate physical chemistry laboratory. Application of standard evaluation techniques to the spectrum yields ground electronic-state molecular parameters in good agreement with literature…
Yoshiki, Wataru; Chen-Jinnai, Akitoshi; Tetsumoto, Tomohiro; Tanabe, Takasumi
2015-11-30
We report the first experimental observation of an energy oscillation between two coupled ultra-high Q whispering gallery modes in the time domain. Two counter-propagating whispering gallery modes in a silica toroid microcavity were employed for this purpose. The combination of a large coupling coefficient between the two modes and an ultra-high Q factor, which creates a large Γ value of > 10, results in a clear energy oscillation. Our measurement is based on a drop-port measurement technique, which enables us to observe the light energy in the two modes directly. The oscillation period measured in the time domain precisely matched that inferred from mode splitting in the frequency domain, and the measured results showed excellent agreement with results calculated with the developed numerical model.
Analysis of neon soft x-ray spectra from short-pulse laser-produced plasmas
International Nuclear Information System (INIS)
Abare, A.C.; Keane, C.J.; Crane, J.K.; DaSilva, L.B.; Lee, R.W.; Perry, M.D.; Falcone, R.W.
1993-04-01
We report preliminary results from the analysis of streaked soft x-ray neon spectra a gas jet target. In obtained from the interaction of a picosecond Nd:glass laser with these experiments streaked spectra show prompt harmonic emission followed by longer time duration soft x-ray line emission. The majority of the line emission observed was found to originate from Li- and Be-like Ne and the major transitions in the observed spectra have been identified. Li-like emission lines were observed to decay faster in time than Be-like transitions, suggesting that recombination is taking place. Line ratios of n=4-2 and n=3-2 transitions supported the view that these lines were optically thin and thick, respectively. The time history of Li-like Ne 2p-4d and 2p-3d lines is in good agreement with a simple adiabatic expansion model coupled to a time dependent collisional-radiative code. Further x-ray spectroscopic analysis is underway which is aimed at diagnosing plasma conditions and assessing the potential of this recombining neon plasma as a quasi-steady-state recombination x-ray laser medium
Strong spin-phonon coupling in infrared and Raman spectra of SrMnO.sub.3./sub..
Czech Academy of Sciences Publication Activity Database
Kamba, Stanislav; Goian, Veronica; Skoromets, Volodymyr; Hejtmánek, Jiří; Bovtun, Viktor; Kempa, Martin; Borodavka, Fedir; Vaněk, Přemysl; Belik, A.A.; Lee, J.H.; Pacherová, Oliva; Rabe, K.M.
2014-01-01
Roč. 89, č. 6 (2014), "064308-1"-"064308-9" ISSN 1098-0121 R&D Projects: GA MŠk LH13048; GA ČR GAP204/12/1163; GA MŠk LD12026; GA ČR GP14-14122P Institutional support: RVO:68378271 Keywords : multiferroics * spin-phonon coupling * infrared and Raman spectra Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.736, year: 2014
Energy Technology Data Exchange (ETDEWEB)
Malerba, M.; De Angelis, F., E-mail: francesco.deangelis@iit.it [Istituto Italiano di Tecnologia, Via Morego, 30, I-16163 Genova (Italy); Ongarello, T.; Paulillo, B.; Manceau, J.-M.; Beaudoin, G.; Sagnes, I.; Colombelli, R., E-mail: raffaele.colombelli@u-psud.fr [Centre for Nanoscience and Nanotechnology (C2N Orsay), CNRS UMR9001, Univ. Paris Sud, Univ. Paris Saclay, 91405 Orsay (France)
2016-07-11
We report a crucial step towards single-object cavity electrodynamics in the mid-infrared spectral range using resonators that borrow functionalities from antennas. Room-temperature strong light-matter coupling is demonstrated in the mid-infrared between an intersubband transition and an extremely reduced number of sub-wavelength resonators. By exploiting 3D plasmonic nano-antennas featuring an out-of-plane geometry, we observed strong light-matter coupling in a very low number of resonators: only 16, more than 100 times better than what reported to date in this spectral range. The modal volume addressed by each nano-antenna is sub-wavelength-sized and it encompasses only ≈4400 electrons.
Energy Technology Data Exchange (ETDEWEB)
Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /York U., Canada /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.
2009-11-01
We determine the strong coupling constant {alpha}{sub s} and its energy dependence from the p{sub T} dependence of the inclusive jet cross section in p{bar p} collisions at {radical}s = 1.96 TeV. The strong coupling constant is determined over the transverse momentum range 50 < p{sub T} < 145 GeV. Using perturbative QCD calculations to order {Omicron}({alpha}{sub s}{sup 3}) combined with {Omicron}({alpha}{sub s}{sup 4}) contributions from threshold corrections, we obtain {alpha}{sub s}(M{sub Z}) = 0.1173{sub -0.0049}{sup +0.0041}. This is the most precise result obtained at a hadron-hadron collider.
Arakawa, Naoya
2016-11-01
I propose the emergence of the spin-orbital-coupled vector chirality in a nonfrustrated Mott insulator with the strong spin-orbit coupling due to a b -plane's inversion-symmetry (IS) breaking. I derive the superexchange interactions for a t2 g-orbital Hubbard model on a square lattice with the strong spin-orbit coupling and the IS-breaking-induced hopping integrals, and explain the microscopic origins of the Dzyaloshinsky-Moriya (DM) -type and the Kitaev-type interactions. Then, by adopting the mean-field approximation to a minimal model including only the Heisenberg-type and the DM-type nearest-neighbor interactions, I show that the IS breaking causes the spin-orbital-coupled chirality as a result of stabilizing the screw state. I also highlight the limit of the hard-pseudospin approximation in discussing the stability of the screw states in the presence of both the DM-type and the Kitaev-type interactions, and discuss its meaning. I finally discuss the effects of tetragonal crystal field and Jeff=3/2 states, and the application to the iridates near the [001 ] surface of Sr2IrO4 and the interface between Sr2IrO4 and Sr3Ir2O7 .
Energy Technology Data Exchange (ETDEWEB)
Abazov, V.M. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Abbott, B. [University of Oklahoma, Norman, OK 73019 (United States); Acharya, B.S. [Tata Institute of Fundamental Research, Mumbai (India); Adams, M. [University of Illinois at Chicago, Chicago, IL 60607 (United States); Adams, T. [Florida State University, Tallahassee, FL 32306 (United States); Alexeev, G.D. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Alkhazov, G. [Petersburg Nuclear Physics Institute, St. Petersburg (Russian Federation); Alton, A. [University of Michigan, Ann Arbor, MI 48109 (United States); Alverson, G. [Northeastern University, Boston, MA 02115 (United States); Askew, A. [Florida State University, Tallahassee, FL 32306 (United States); Atkins, S. [Louisiana Tech University, Ruston, LA 71272 (United States); Augsten, K. [Czech Technical University in Prague, Prague (Czech Republic); Avila, C. [Universidad de los Andes, Bogota (Colombia); Badaud, F. [LPC, Universite Blaise Pascal, CNRS/IN2P3, Clermont (France); Bagby, L.; Baldin, B. [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Bandurin, D.V. [Florida State University, Tallahassee, FL 32306 (United States); Banerjee, S. [Tata Institute of Fundamental Research, Mumbai (India); Barberis, E. [Northeastern University, Boston, MA 02115 (United States); Baringer, P. [University of Kansas, Lawrence, KS 66045 (United States); and others
2012-11-15
We present a measurement of the average value of a new observable at hadron colliders that is sensitive to QCD dynamics and to the strong coupling constant, while being only weakly sensitive to parton distribution functions. The observable measures the angular correlations of jets and is defined as the number of neighboring jets above a given transverse momentum threshold which accompany a given jet within a given distance {Delta}R in the plane of rapidity and azimuthal angle. The ensemble average over all jets in an inclusive jet sample is measured and the results are presented as a function of transverse momentum of the inclusive jets, in different regions of {Delta}R and for different transverse momentum requirements for the neighboring jets. The measurement is based on a data set corresponding to an integrated luminosity of 0.7 fb{sup -1} collected with the D0 detector at the Fermilab Tevatron Collider in pp{sup Macron} collisions at {radical}(s)=1.96 TeV. The results are well described by a perturbative QCD calculation in next-to-leading order in the strong coupling constant, corrected for non-perturbative effects. From these results, we extract the strong coupling and test the QCD predictions for its running over a range of momentum transfers of 50-400 GeV.
Sodium hydride clusters in solid hydrogen and neon: infrared spectra and theoretical calculations.
Wang, Xuefeng; Andrews, Lester
2007-08-02
Laser-ablated sodium atom reactions with H2 have been investigated in solid molecular hydrogens and neon. The NaH molecule and (NaH)2,3,4 clusters were identified by IR spectra with isotopic substitution (HD and D2) and comparison to frequencies calculated by density functional theory and the MP2 method. The use of para-hydrogen enriched samples provides evidence for a (H2)nNaH subcomplex surrounded by the solid hydrogen matrix cage. The ionic rhombic (NaH)2 dimer is characterized by strong absorptions at 761.7, 759.1, and 757.0 cm(-1), respectively, in solid neon, para-hydrogen, and normal hydrogen matrices. The cyclic sodium hydride trimer and tetramer clusters are also observed. Although the spontaneous reaction of two Li and H2 to form (LiH)2 occurs on annealing in solid H2, the formation of (NaH)2 requires near uv photoexcitation.
The solar wind neon abundance observed with ACE/SWICS and ULYSSES/SWICS
International Nuclear Information System (INIS)
Shearer, Paul; Raines, Jim M.; Lepri, Susan T.; Thomas, Jonathan W.; Gilbert, Jason A.; Landi, Enrico; Zurbuchen, Thomas H.; Von Steiger, Rudolf
2014-01-01
Using in situ ion spectrometry data from ACE/SWICS, we determine the solar wind Ne/O elemental abundance ratio and examine its dependence on wind speed and evolution with the solar cycle. We find that Ne/O is inversely correlated with wind speed, is nearly constant in the fast wind, and correlates strongly with solar activity in the slow wind. In fast wind streams with speeds above 600 km s –1 , we find Ne/O = 0.10 ± 0.02, in good agreement with the extensive polar observations by Ulysses/SWICS. In slow wind streams with speeds below 400 km s –1 , Ne/O ranges from a low of 0.12 ± 0.02 at solar maximum to a high of 0.17 ± 0.03 at solar minimum. These measurements place new and significant empirical constraints on the fractionation mechanisms governing solar wind composition and have implications for the coronal and photospheric abundances of neon and oxygen. The results are made possible by a new data analysis method that robustly identifies rare elements in the measured ion spectra. The method is also applied to Ulysses/SWICS data, which confirms the ACE observations and extends our view of solar wind neon into the three-dimensional heliosphere.
The solar wind neon abundance observed with ACE/SWICS and ULYSSES/SWICS
Energy Technology Data Exchange (ETDEWEB)
Shearer, Paul; Raines, Jim M.; Lepri, Susan T.; Thomas, Jonathan W.; Gilbert, Jason A.; Landi, Enrico; Zurbuchen, Thomas H. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Von Steiger, Rudolf [International Space Science Institute, Hallerstrasse 6, CH-3012 Bern (Switzerland)
2014-07-01
Using in situ ion spectrometry data from ACE/SWICS, we determine the solar wind Ne/O elemental abundance ratio and examine its dependence on wind speed and evolution with the solar cycle. We find that Ne/O is inversely correlated with wind speed, is nearly constant in the fast wind, and correlates strongly with solar activity in the slow wind. In fast wind streams with speeds above 600 km s{sup –1}, we find Ne/O = 0.10 ± 0.02, in good agreement with the extensive polar observations by Ulysses/SWICS. In slow wind streams with speeds below 400 km s{sup –1}, Ne/O ranges from a low of 0.12 ± 0.02 at solar maximum to a high of 0.17 ± 0.03 at solar minimum. These measurements place new and significant empirical constraints on the fractionation mechanisms governing solar wind composition and have implications for the coronal and photospheric abundances of neon and oxygen. The results are made possible by a new data analysis method that robustly identifies rare elements in the measured ion spectra. The method is also applied to Ulysses/SWICS data, which confirms the ACE observations and extends our view of solar wind neon into the three-dimensional heliosphere.
Energy Technology Data Exchange (ETDEWEB)
Foulk, James W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Alleman, Coleman N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mota, Alejandro [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lim, Hojun [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Littlewood, David John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bergel, Guy Leshem [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Popova, Evdokia [Georgia Inst. of Technology, Atlanta, GA (United States). Woodruff School of Mechanical Engineering; Montes de Oca Zapiain, David [Georgia Inst. of Technology, Atlanta, GA (United States). Woodruff School of Mechanical Engineering; Kalidindi, Suryanarayana Raju [Georgia Inst. of Technology, Atlanta, GA (United States). Woodruff School of Mechanical Engineering; Ernst, Corey [Elemental Technologies, Provo, UT (United States)
2017-09-01
The heterogeneity in mechanical fields introduced by microstructure plays a critical role in the localization of deformation. To resolve this incipient stage of failure, it is therefore necessary to incorporate microstructure with sufficient resolution. On the other hand, computational limitations make it infeasible to represent the microstructure in the entire domain at the component scale. In this study, the authors demonstrate the use of concurrent multi- scale modeling to incorporate explicit, finely resolved microstructure in a critical region while resolving the smoother mechanical fields outside this region with a coarser discretization to limit computational cost. The microstructural physics is modeled with a high-fidelity model that incorporates anisotropic crystal elasticity and rate-dependent crystal plasticity to simulate the behavior of a stainless steel alloy. The component-scale material behavior is treated with a lower fidelity model incorporating isotropic linear elasticity and rate-independent J 2 plas- ticity. The microstructural and component scale subdomains are modeled concurrently, with coupling via the Schwarz alternating method, which solves boundary-value problems in each subdomain separately and transfers solution information between subdomains via Dirichlet boundary conditions. Beyond cases studies in concurrent multiscale, we explore progress in crystal plastic- ity through modular designs, solution methodologies, model verification, and extensions to Sierra/SM and manycore applications. Advances in conformal microstructures having both hexahedral and tetrahedral workflows in Sculpt and Cubit are highlighted. A structure-property case study in two-phase metallic composites applies the Materials Knowledge System to local metrics for void evolution. Discussion includes lessons learned, future work, and a summary of funded efforts and proposed work. Finally, an appendix illustrates the need for two-way coupling through a single degree of
Pixley, J. H.; Cole, William S.; Spielman, I. B.; Rizzi, Matteo; Das Sarma, S.
2017-10-01
We study the odd-integer filled Mott phases of a spin-1 Bose-Hubbard chain and determine their fate in the presence of a Raman induced spin-orbit coupling which has been achieved in ultracold atomic gases; this system is described by a quantum spin-1 chain with a spiral magnetic field. The spiral magnetic field initially induces helical order with either ferromagnetic or dimer order parameters, giving rise to a spiral paramagnet at large field. The spiral ferromagnet-to-paramagnet phase transition is in a universality class with critical exponents associated with the divergence of the correlation length ν ≈2 /3 and the order-parameter susceptibility γ ≈1 /2 . We solve the effective spin model exactly using the density-matrix renormalization group, and compare with both a large-S classical solution and a phenomenological Landau theory. We discuss how these exotic bosonic magnetic phases can be produced and probed in ultracold atomic experiments in optical lattices.
Wang, Hai; Toma, Andrea; Wang, Hai-Yu; Bozzola, Angelo; Miele, Ermanno; Haddadpour, Ali; Veronis, Georgios; De Angelis, Francesco; Wang, Lei; Chen, Qi-Dai; Xu, Huai-Liang; Sun, Hong-Bo; Zaccaria, Remo Proietti
2016-07-21
We have investigated the influence of Rabi splitting tuning on the dynamics of strongly coupled J-aggregate/surface plasmon polariton systems. In particular, the Rabi splitting was tuned by modifying the J-aggregate molecule concentration while a polaritonic system was provided by a nanostructure formed by holes array in a golden layer. From the periodic and concentration changes we have identified, through numerical and experimental steady-state analyses, the best geometrical configuration for maximizing Rabi splitting, which was then used for transient absorption measurements. It was found that in transient absorption spectra, under upper band excitation, two bleaching peaks appear when a nanostructured polaritonic pattern is used. Importantly, their reciprocal distance increases upon increase of J-aggregate concentration, a result confirmed by steady-state analysis. In a similar manner it was also found that the lifetime of the upper band is intimately related to the coupling strength. In particular, we argue that with strong coupling strength, i.e. high J-aggregate concentration, a short lifetime of the upper band has to be expected due to the suppression of the bottleneck effect. This result supports the idea that the dynamics of hybrid systems is profoundly dependent on Rabi splitting.
International Nuclear Information System (INIS)
Roiban, R.; Tseytlin, A. A.
2008-01-01
We consider folded (S,J) spinning strings in AdS 5 xS 5 (with one spin component in AdS 5 and a one in S 5 ) corresponding to the Tr(D S Φ J ) operators in the sl(2) sector of the N=4 super Yang-Mills theory in the special scaling limit in which both the string mass ∼√(λ)lnS and J are sent to infinity with their ratio fixed. Expanding in the parameter l=(J/√(λ)lnS) we compute the 2-loop string sigma-model correction to the string energy and show that it agrees with the expression proposed by Alday and Maldacena [J. High Energy Phys. 11 (2007) 019]. We suggest that a resummation of the logarithmic l 2 ln n l terms is necessary in order to establish an interpolation to the weakly coupled gauge-theory results. In the process, we set up a general framework for the calculation of higher loop corrections to the energy of multispin string configurations. In particular, we find that in addition to the direct 2-loop term in the string energy there is a contribution from lower loop order due to a finite 'renormalization' of the relation between the parameters of the classical solution and the fixed spins, i.e., the charges of the SO(2,4)xSO(6) symmetry.
International Nuclear Information System (INIS)
Sherman, A.; Schreiber, M.
1995-01-01
We use the Eliashberg formalism for calculating T c in a model of cuprate perovskites with pairing mediated by both magnons and apex-oxygen vibrations. The influence of strong correlations on the energy spectrum is taken into account in the spin-wave approximation. It is shown that the hole-magnon interaction alone cannot yield high T c . But together with a moderate hole-phonon interaction it does lead to d-wave superconductivity at temperatures and hole concentrations observed in cuprates. High T c are connected with a large density of states due to extended Van Hove singularities, a conformity of the two interactions for the d symmetry, and high phonon frequencies
Simulations of Neon Pellets for Plasma Disruption Mitigation in Tokamaks
Bosviel, Nicolas; Samulyak, Roman; Parks, Paul
2017-10-01
Numerical studies of the ablation of neon pellets in tokamaks in the plasma disruption mitigation parameter space have been performed using a time-dependent pellet ablation model based on the front tracking code FronTier-MHD. The main features of the model include the explicit tracking of the solid pellet/ablated gas interface, a self-consistent evolving potential distribution in the ablation cloud, JxB forces, atomic processes, and an improved electrical conductivity model. The equation of state model accounts for atomic processes in the ablation cloud as well as deviations from the ideal gas law in the dense, cold layers of neon gas near the pellet surface. Simulations predict processes in the ablation cloud and pellet ablation rates and address the sensitivity of pellet ablation processes to details of physics models, in particular the equation of state.
Directory of Open Access Journals (Sweden)
James Avery Sauls
2015-06-01
Full Text Available Recent theories of Sr2RuO4 based on the interplay of strong interactions, spin-orbit coupling and multi-band anisotropy predict chiral or helical ground states with strong anisotropy of the pairing states, with deep minima in the excitation gap, as well as strong phase anisotropy for the chiral ground state. We develop time-dependent mean field theory to calculate the Bosonic spectrum for the class of 2D chiral superconductors spanning 3He-A to chiral superconductors with strong anisotropy. Chiral superconductors support a pair of massive Bosonic excitations of the time-reversed pairs labeled by their parity under charge conjugation. These modes are degenerate for 2D 3He-A. Crystal field anisotropy lifts the degeneracy. Strong anisotropy also leads to low-lying Fermions, and thus to channels for the decay of the Bosonic modes. Selection rules and phase space considerations lead to large asymmetries in the lifetimes and hybridization of the Bosonic modes with the continuum of un-bound Fermion pairs. We also highlight results for the excitation of the Bosonic modes by microwave radiation that provide clear signatures of the Bosonic modes of an anisotropic chiral ground state.
Leupold, D; Ehlert, J; Irrgang, K D; Renger, G; Lokstein, H
2002-01-01
Stepwise two-photon excitation of chlorophyll a and b in the higher plant main light-harvesting complex (LHC II) and the minor complex CP29 (as well as in organic solution) with 100-fs pulses in the Q/sub y/ region results in a weak blue fluorescence. The dependence of the spectral shape of the blue fluorescence on excitation wavelength offers a new approach to elucidate the long-standing problem of the origin of spectral "chlorophyll forms" in pigment-protein complexes, in particular the characterization of chlorophyll a/b-heterodimers. As a first result we present evidence for the existence of strong chlorophyll a/b-interactions (excitonically coupled transitions at 650 and 680 nm) in LHC II at ambient temperature. In comparison with LHC II, the experiments with CP29 provide further evidence that the lowest energy chlorophyll a transition (at ~680 nm) is not excitonically coupled to chlorophyll b. (22 refs).
X-ray spectroscopy with Z-pinch neon plasmas
Mehlman, G.; Burkhalter, P. G.; Newman, D. A.; Stephanakis, S. J.; Young, F. C.
1986-07-01
Spatially resolved soft x ray spectra were collected for neon plasmas produced by imploding hollow annular gas puffs with MA level driving currents. The Z pinched imploded plasmas were studied for different rise-time currents produced with or without the use of a plasma erosion opening switch (PEOS). Selected spectrograms were processed and analyzed to obtain absolute energies for the radiation emitted in the Neon 1X and Ne X discrete transitions as well as for total emission over the spectral range 900-1600 eV. The energy radiated for typical shots with or without the PEOS is compared particularly for the predominant alpha transitions of both ions. Also, line widths for the alpha and beta transitions of both ions are determined. X-ray spectroscopy with established x-ray film calibrations and crystal responses has provided absolute intensities for neon K-shell x-rays from gas-jet implosions. Most (90%) of the line radiation is contained in the He-alpha and L-alpha lines of neon. The use of a PEOS to reduce the current risetime and eliminate prepulse produces spectra with less continuu m background and with lines that are narrower by a factor of two. With the PEOS and 1-MA peak driving current, the total radiated energy from 900 to 1600 eV is 1.2 kJ with about 75% of this emission in line radiation. Without the PEOS and with 1.2 MA peak driving current, the total radiated energy in this energy region increases to 2.5 kJ, but only about 45% is in line radiation.
International Nuclear Information System (INIS)
Wang, Yinling; Wang, Zhangcui; Wu, Xiaoqin; Liu, Xiaowang; Li, Maoguo
2016-01-01
Highlights: • CoAl-LDHs were synthesized on the surface of graphene oxide in situ. • The oxygen reduction reaction activity of the catalyst was investigated. • The synergistic effect between CoAl-LDHs and rGO is discussed in detail. • The roles of Co 2+ in the LDHs were clarified. - Abstract: Precious metal-free electrocatalysts with high efficiency and durability for the oxygen reduction reaction (ORR) are strongly desired in the field of energy technology. Herein, the CoAl layered double hydroxides (CoAl-LDHs)/reduced graphene oxide (rGO) composites were successfully prepared by growing CoAl-LDHs on the surface of GO in situ via coprecipitation and subsequently hydrothermal treatment. The structure, composition, morphology and ORR catalytic activity of the CoAl-LDHs/rGO composites were investigated as a function of mass ratios of CoAl-LDHs and GO. The results show that there is an optimum mass ratio of CoAl-LDHs and GO (w CoAl-LDHs :w GO = 1:5) for the ORR catalytic activity, where the electron transfer number for ORR at the CoAl-LDHs/rGO composites reaches to 3.5, closing to the full four-electron process. The synergistic effect between CoAl-LDHs and rGO is discussed in detail and the discussion is instructive for the construction of the better transition metal oxides/carbon composite-based ORR catalysts.
International Nuclear Information System (INIS)
Min, Shixiong; Hou, Jianhua; Lei, Yonggang; Ma, Xiaohua; Lu, Gongxuan
2017-01-01
Highlights: • TiO 2 /GQDs composites were prepared by a facile one-step hydrothermal method. • GQDs were strongly coupled onto the surface of TiO 2 nanoparticles by this method. • The TiO 2 /GQDs showed enhanced light absorption and charge separation efficiency. • The TiO 2 /GQDs exhibited higher photocatalytic H 2 evolution activity than pure TiO 2 . • GQDs play synergistic roles by acting as both photosensitizer and electron acceptor. - Abstract: The coupling of semiconductor photocatalysts with graphene quantum dots (GQDs) has been proven to be an effective strategy to enhance the photocatalytic and photoelectrical conversion performances of the resulted composites; however, the preparation of semiconductor/GQDs composites usually involves several time-inefficient and tedious post-treatment steps. Herein, we present a facile one-step hydrothermal route for the preparation of GQDs coupled TiO 2 (TiO 2 /GQDs) photocatalysts using 1,3,6-trinitropyrene (TNP) as the sole precursor of GQDs. During the hydrothermal process, TNP molecules undergo an intramolecular fusion to form GQDs, which simultaneously decorate on the surface of TiO 2 nanoparticles, leading to a strong surface interaction between the two components. The effective coupling of GQDs on TiO 2 can effectively extend the light absorption of the TiO 2 to visible region and enhance the charge separation efficiency of TiO 2 /GQDs composites as a result of GQDs acting as a photosensitizer and an excellent electron acceptor. These key advances make the TiO 2 /GQDs photocatalyst highly active towards the H 2 evolution reaction, resulting in 7 and 3 times higher H 2 evolution rate and photocurrent response at optimal GQDs content than TiO 2 alone, respectively. This study provides a new methodology for the development of high-performance GQDs modified semiconductor photocatalysts for energy conversion applications.
NEON's Mobile Deployment Platform: A Resource for Community Research
Sanclements, M.
2017-12-01
Here we provide an update on construction of the five NEON Mobile Deployment Platforms (MDPs) as well as a description of the infrastructure and sensors available to researchers in the near future. Additionally, we include information (i.e. timelines and procedures) on requesting MDPs for PI led projects. The MDPs will provide the means to observe stochastic or spatially important events, gradients, or quantities that cannot be reliably observed using fixed location sampling (e.g. fires and floods). Due to the transient temporal and spatial nature of such events, the MDPs are designed to accommodate rapid deployment for time periods up to 1 year. Broadly, the MDPs are comprised of infrastructure and instrumentation capable of functioning individually or in conjunction with one another to support observations of ecological change, as well as education, training and outreach. More specifically, the MDPs include the capability to make tower based measures of ecosystem exchange, radiation, and precipitation in conjunction with baseline soils data such as CO2 flux, and soil temperature and moisture. An aquatics module is also available with the MDP to facilitate research integrating terrestrial and aquatic processes. Ultimately, the NEON MDPs provide a tool for linking PI led research to the continental scale data sets collected by NEON.
Charge radii of neon isotopes across the sd neutron shell
Marinova, K; Kowalska, M; Kotrotsios, G; Kloos, S; Neugart, R; Blaum, K; Simon, H; Keim, M; Lievens, P; Wilbert, S; Kappertz, S
2011-01-01
We report on the changes in mean square charge radii of unstable neon nuclei relative to the stable (20)Ne, based on the measurement of optical isotope shifts. The studies were carried out using collinear laser spectroscopy on a fast beam of neutral neon atoms. High sensitivity on short-lived isotopes was achieved thanks to nonoptical detection based on optical pumping and state-selective collisional ionization, which was complemented by an accurate determination of the beam kinetic energy. The new results provide information on the structural changes in the sequence of neon isotopes all across the neutron sd shell, ranging from the proton drip line nucleus and halo candidate (17)Ne up to the neutron-rich (28)Ne in the vicinity of the ``island of inversion.{''} Within this range the charge radius is smallest for (24)Ne with N = 14 corresponding to the closure of the neutron d(5/2) shell, while it increases toward both neutron shell closures, N = 8 and N = 20. The general trend of the charge radii correlates w...
Reuvekamp, Patrick; Caslin, Kevin; Guguchia, Zurab; Keller, Hugo; Kremer, Reinhard K; Simon, Arndt; Köhler, Jürgen; Bussmann-Holder, Annette
2015-07-08
EuTiO3 exhibits strong magneto-electric coupling at the onset of antiferromagnetic order below TN = 5.7 K. The dielectric permittivity drops at TN by 7% and recovers to normal values with increasing magnetic field. This effect is shown to stem from tiny lattice effects as seen in magnetostriction data which directly affect the soft optic mode and its polarizability coordinate. By combining experimental results with theory we show that marginal changes in the lattice parameter of the order of 0.01% have a more than 1000% effect on the transverse optic soft mode of ETO and thus easily induce a ferroelectric instability.
Directory of Open Access Journals (Sweden)
Maxim Goryachev
2018-04-01
Full Text Available A quartz Bulk Acoustic Wave resonator is designed to coherently trap phonons in such a way that they are well confined and immune to suspension losses so they exhibit extremely high acoustic Q-factors at low temperature, with Q × f products of order 10 18 Hz. In this work we couple such a resonator to a Superconducting Quantum Interference Device (SQUID amplifier and investigate effects in the strong signal regime. Both parallel and series connection topologies of the system are investigated. The study reveals significant non-Duffing response that is associated with the nonlinear characteristics of Josephson junctions. The nonlinearity provides quasi-periodic structure of the spectrum in both incident power and frequency. The result gives an insight into the open loop behaviour of a future Cryogenic Quartz Oscillator in the strong signal regime.
Two-photon-induced x-ray emission in neon atoms
International Nuclear Information System (INIS)
Sun Yuping; Wang Chuankui; Rinkevicius, Zilvinas; Gel'mukhanov, Faris; Carniato, Stephane; Simon, Marc; Taieeb, Richard
2010-01-01
We investigated the resonant x-ray emission from a neon atom induced by the two-photon population of a double-core-hole excited state. Two qualitatively different schemes of this process are studied: The first one involves an off-resonant intermediate single-core-hole state; the second scheme passes through a resonant core-ionized intermediate state. The numerical simulations of the resonant x-ray emission performed for different peak intensities and pulse durations show significant population of the double-core-hole final states. Therefore, rather strong two-photon absorption-induced x-ray emission is predicted for both studied schemes. Thus, high counting rates in experimental measurements are expected.
Scintillation yield and time dependence from electronic and nuclear recoils in liquid neon
Lippincott, W. H.; Coakley, K. J.; Gastler, D.; Kearns, E.; McKinsey, D. N.; Nikkel, J. A.
2012-07-01
We have performed measurements of scintillation light in liquid neon, observing a signal yield in our detector as high as (3.5 ± 0.4) photoelectrons/keV. We measure pulse shape discrimination efficiency between electronic and nuclear recoils in liquid neon from 50 to 300 keV nuclear recoil energy. We also measure the Leff parameter in liquid neon between 30 and 370 keV nuclear recoil energy, observing an average Leff=0.24 above 50 keV. We observe a dependence of the scintillation time distribution and signal yield on the pressure and temperature of the liquid neon.
Endrizzi, S.
2011-12-01
GEOtop is a small scale grid-based model that couples the soil heat and water budgets, represents the energy exchange with the atmosphere considering the radiative and turbulent fluxes, and describes the subsurface water flow in its fully three-dimensional nature. In particular, the model reproduces the strong coupling between water and energy balance during soil freezing and thawing processes, considering the highly non-linear heat capacity effect resulting from phase change. In addition, it describes the water and energy budgets in the snow cover, represents blowing snow, and models the temporal evolution of the snow depth and, therefore, its effect on soil temperature. Infiltration in frozen soil and runoff are also represented. Vegetation effects are considered, in particular as regards snow interception, trapping, and the interactions with turbulent and radiative heat exchange. GEOtop is therefore a very useful tool in several applications that involve permafrost and seasonally-frozen soils, both in high altitude and latitude regions. In particular, GEOtop allows evaluating the effects of water lateral transport in the freezing/thawing process, effects that are often neglected, but may be significant. Applications are shown for i) a typical peat-covered arctic environment, where the position of the frost table controls the runoff production rate, due to the strong decrease of the soil hydraulic conductivity with depth; and ii) an alpine site, where borehole data are used to test the model and the effect of the upslope drainage distance is studied.
Chen, Yuting; Yang, Taiqun; Pan, Haifeng; Yuan, Yufeng; Chen, Li; Liu, Mengwei; Zhang, Kun; Zhang, Sanjun; Wu, Peng; Xu, Jianhua
2014-02-05
Using carboxylate-protected silver nanoclusters (Ag-carboxylate NCs) as a model, we separately investigated the contribution of the ligand shell and the metal core to understand the nature of photoluminescence of Ag NCs. A new Ag(0)NCs@Ag(I)-carboxylate complex core-shell structural model has been proposed. The emission from the Ag-carboxylate NCs could be attributed to ligand-to-metal-metal charge transfer from Ag(I)-carboxylate complexes (the oxygen atom in the carboxylate ligands to the Ag(I) ions) to the Ag atoms and subsequent radiative relaxation. Additionally, we found that the emission wavelength of the Ag NCs depends on the excitation wavelength implying a strong coupling between surface plasmon and emitter in Ag NCs. The strong coupling between the surface plasmon and the emitter determines the quantum yield and lifetime. The emission mechanism of Ag NCs and its relation to the organic templates and metal cores were clearly clarified. The results should stimulate additional experimental and theoretical research on the molecular-level design of luminescent metal probes for optoelectronics and other applications.
Sukharev, Maxim; Pachter, Ruth
2018-03-01
We study theoretically the optical response of a WS2 monolayer located near periodic metal nanostructured arrays in two and three dimensions. The emphasis of the simulations is on the strong coupling between excitons supported by WS2 and surface plasmon-polaritons supported by various periodic plasmonic interfaces. It is demonstrated that a monolayer of WS2 placed in close proximity of periodic arrays of either slits or holes results in a Rabi splitting of the corresponding surface plasmon-polariton resonance as revealed in calculated transmission and reflection spectra. The nonlinear regime, at which the few-layer WS2 exhibits experimentally third harmonic generation (THG), is studied in detail. Monolayer transition metal dichalcogenides (TMDs) do not exhibit THG because they are non-centrosymmetric, but here we use the monolayer as an approximation to a thin TMD nanostructure. We show that in the strong coupling regime the third harmonic signal is significantly affected by plasmon-polaritons and the symmetry of hybrid exciton-plasmon modes. It is also shown that the local electromagnetic field induced by plasmons is the major contributor to the enhancement of the third harmonic signal in three dimensions. The local electromagnetic fields resulting from the third harmonic generation are greatly localized and highly sensitive to the environment, thus making it a great tool for nano-probes.
Kim, Jong Min; Kim, Sung; Hwang, Sung Won; Kim, Chang Oh; Shin, Dong Hee; Kim, Ju Hwan; Jang, Chan Wook; Kang, Soo Seok; Hwang, Euyheon; Choi, Suk-Ho; El-Gohary, Sherif H.; Byun, Kyung Min
2018-02-01
Recently, we have demonstrated that excitation of plasmon-polaritons in a mechanically-derived graphene sheet on the top of a ZnO semiconductor considerably enhances its light emission efficiency. If this scheme is also applied to device structures, it is then expected that the energy efficiency of light-emitting diodes (LEDs) increases substantially and the commercial potential will be enormous. Here, we report that the plasmon-induced light coupling amplifies emitted light by ∼1.6 times in doped large-area chemical-vapor-deposition-grown graphene, which is useful for practical applications. This coupling behavior also appears in GaN-based LEDs. With AuCl3-doped graphene on Ga-doped ZnO films that is used as transparent conducting electrodes for the LEDs, the average electroluminescence intensity is 1.2–1.7 times enhanced depending on the injection current. The chemical doping of graphene may produce the inhomogeneity in charge densities (i.e., electron/hole puddles) or roughness, which can play a role as grating couplers, resulting in such strong plasmon-enhanced light amplification. Based on theoretical calculations, the plasmon-coupled behavior is rigorously explained and a method of controlling its resonance condition is proposed.
YBa{sub 2}Cu{sub 3}O{sub 7} microwave resonators for strong collective coupling with spin ensembles
Energy Technology Data Exchange (ETDEWEB)
Ghirri, A., E-mail: alberto.ghirri@nano.cnr.it [Istituto Nanoscienze - CNR, Centro S3, via Campi 213/a, 41125 Modena (Italy); Bonizzoni, C.; Affronte, M. [Dipartimento Fisica, Informatica e Matematica, Università di Modena e Reggio Emilia and Istituto Nanoscienze - CNR, Centro S3, via Campi 213/a, 41125 Modena (Italy); Gerace, D.; Sanna, S. [Dipartimento di Fisica, Università di Pavia, via Bassi 6, 27100 Pavia (Italy); Cassinese, A. [CNR-SPIN and Dipartimento di Fisica, Università di Napoli Federico II, 80138 Napoli (Italy)
2015-05-04
Coplanar microwave resonators made of 330 nm-thick superconducting YBa{sub 2}Cu{sub 3}O{sub 7} have been realized and characterized in a wide temperature (T, 2–100 K) and magnetic field (B, 0–7 T) range. The quality factor (Q{sub L}) exceeds 10{sup 4} below 55 K and it slightly decreases for increasing fields, remaining 90% of Q{sub L}(B=0) for B = 7 T and T = 2 K. These features allow the coherent coupling of resonant photons with a spin ensemble at finite temperature and magnetic field. To demonstrate this, collective strong coupling was achieved by using di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium organic radical placed at the magnetic antinode of the fundamental mode: the in-plane magnetic field is used to tune the spin frequency gap splitting across the single-mode cavity resonance at 7.75 GHz, where clear anticrossings are observed with a splitting as large as ∼82 MHz at T = 2 K. The spin-cavity collective coupling rate is shown to scale as the square root of the number of active spins in the ensemble.
Experimental comparison of EMC effect in the anti νn and anti νp interactions in neon nucleus
International Nuclear Information System (INIS)
Asratyan, A.E.; Efremenko, V.I.; Fedotov, A.V.
1985-01-01
In the framework of the method used to separate the antiν and antiνp interactions in the neon nucleus, a strong distinction of the quantity Rsub(Ne)(x)=(dσsup(antiνn)/dx)/(dσsup(antiνp)/dx) measured in this anti νNe experiment from the analogous quantity Rsub(D)(x) obtained earlier in a deuterium experimentis found. This difference can be attributed to the difference between the magnitudes of the EMC effect in the anti νn and anti νp scattering
Energy Technology Data Exchange (ETDEWEB)
Min, Shixiong, E-mail: sxmin@nun.edu.cn [School of Chemistry and Chemical Engineering, Beifang University of Nationalities, Yinchuan, 750021, Ningxia Province (China); Hou, Jianhua; Lei, Yonggang; Ma, Xiaohua [School of Chemistry and Chemical Engineering, Beifang University of Nationalities, Yinchuan, 750021, Ningxia Province (China); Lu, Gongxuan [State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China)
2017-02-28
Highlights: • TiO{sub 2}/GQDs composites were prepared by a facile one-step hydrothermal method. • GQDs were strongly coupled onto the surface of TiO{sub 2} nanoparticles by this method. • The TiO{sub 2}/GQDs showed enhanced light absorption and charge separation efficiency. • The TiO{sub 2}/GQDs exhibited higher photocatalytic H{sub 2} evolution activity than pure TiO{sub 2}. • GQDs play synergistic roles by acting as both photosensitizer and electron acceptor. - Abstract: The coupling of semiconductor photocatalysts with graphene quantum dots (GQDs) has been proven to be an effective strategy to enhance the photocatalytic and photoelectrical conversion performances of the resulted composites; however, the preparation of semiconductor/GQDs composites usually involves several time-inefficient and tedious post-treatment steps. Herein, we present a facile one-step hydrothermal route for the preparation of GQDs coupled TiO{sub 2} (TiO{sub 2}/GQDs) photocatalysts using 1,3,6-trinitropyrene (TNP) as the sole precursor of GQDs. During the hydrothermal process, TNP molecules undergo an intramolecular fusion to form GQDs, which simultaneously decorate on the surface of TiO{sub 2} nanoparticles, leading to a strong surface interaction between the two components. The effective coupling of GQDs on TiO{sub 2} can effectively extend the light absorption of the TiO{sub 2} to visible region and enhance the charge separation efficiency of TiO{sub 2}/GQDs composites as a result of GQDs acting as a photosensitizer and an excellent electron acceptor. These key advances make the TiO{sub 2}/GQDs photocatalyst highly active towards the H{sub 2} evolution reaction, resulting in 7 and 3 times higher H{sub 2} evolution rate and photocurrent response at optimal GQDs content than TiO{sub 2} alone, respectively. This study provides a new methodology for the development of high-performance GQDs modified semiconductor photocatalysts for energy conversion applications.
Stimulated Superconductivity at Strong Coupling
Energy Technology Data Exchange (ETDEWEB)
Bao, Ning; Dong, Xi; Silverstein, Eva; Torroba, Gonzalo; /Stanford U., ITP /Stanford U., Phys. Dept. /SLAC
2011-08-12
Stimulating a system with time dependent sources can enhance instabilities, thus increasing the critical temperature at which the system transitions to interesting low-temperature phases such as superconductivity or superfluidity. After reviewing this phenomenon in non-equilibrium BCS theory (and its marginal fermi liquid generalization) we analyze the effect in holographic superconductors. We exhibit a simple regime in which the transition temperature increases parametrically as we increase the frequency of the time-dependent source.
Multiple pulse traveling wave excitation of neon-like germanium
International Nuclear Information System (INIS)
Moreno, J. C.; Nilsen, J.; Silva, L. B. da
1995-01-01
Traveling wave excitation has been shown to significantly increase the output intensity of the neon-like germanium x-ray laser. The driving laser pulse consisted of three 100 ps Gaussian laser pulses separated by 400 ps. Traveling wave excitation was employed by tilting the wave front of the driving laser by 45 degrees to match the propagation speed of the x-ray laser photons along the length of the target. We show results of experiments with the traveling wave, with no traveling wave, and against the traveling wave and comparisons to a numerical model. Gain was inferred from line intensity measurements at two lengths
Erosion of solid neon by keV electrons
DEFF Research Database (Denmark)
Schou, Jørgen; Børgesen, P.; Ellegaard, Ole
1986-01-01
The erosion of solid neon by keV electrons has been studied experimentally and theoretically. Electronic sputtering as well as temperature-enhanced sublimation are investigated by a frequency-change measurement on a quartz crystal or in some cases by the change in intensity of reflected electrons....... The erosion yield increases with increasing temperature for substrate temperatures above 7K. Below this temperature sputtering via electronic transitions is the dominant process. The yield shows a clear minimum for film thicknesses about (5-7)×1016 Ne atoms/cm2 for 2-keV electrons. The sputtering yield...
Small, David W; Head-Gordon, Martin
2017-07-14
The Coupled Cluster Valence Bond (CCVB) method, previously presented for closed-shell (CS) systems, is extended to open-shell (OS) systems. The theoretical development is based on embedding the basic OS CCVB wavefunction in a fictitious singlet super-system. This approach reveals that the OS CCVB amplitude equations are quite similar to those of CS CCVB, and thus that OS CCVB requires the same level of computational effort as CS CCVB, which is an inexpensive method. We present qualitatively correct CCVB potential energy curves for all low-lying spin states of P 2 and Mn 2 + . CCVB is successfully applied to the low-lying spin states of some model linear polycarbenes, systems that appear to be a hindrance to standard density functionals. We examine an octa-carbene dimer in a side-by-side orientation, which, in the monomer dissociation limit, exhibits maximal strong correlation over the length of the polycarbene.
Energy Technology Data Exchange (ETDEWEB)
Abbiendi, G.; Braibant, S.; Capiluppi, P.; Ciocca, C.; Cuffiani, M.; Fabbri, F.; Giacomelli, G.; Giacomelli, P.; Marcellini, S.; Michelini, A.; Rossi, A.M. [Universita di Bologna and INFN, Dipartimento di Fisica, Bologna (Italy); Ainsley, C.; Batley, R.J.; Carter, J.R.; Hill, J.C.; Thomson, M.A.; Ward, C.P.; Ward, D.R. [Cavendish Laboratory, Cambridge (United Kingdom); Aakesson, P.F.; Geich-Gimbel, C.; Guenther, P.O.; Kobel, M.; Ludwig, A.; Mader, W.; Quadt, A.; Schumacher, M.; Stahl, A.; Wermes, N. [Universitaet Bonn, Physikalisches Institut, Bonn (Germany); Alexander, G.; Bella, G.; Etzion, E.; Grunhaus, J.; Tsur, E. [Tel Aviv University, Department of Physics and Astronomy, Tel Aviv (Israel); Anagnostou, G.; Bell, P.J.; Charlton, D.G.; Hawkes, C.M.; Jovanovic, P.; Letts, J.; Maettig, P.; O' Neale, S.W.; Turner-Watson, M.F.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wilson, J.A. [University of Birmingham, School of Physics and Astronomy, Birmingham (United Kingdom); Anderson, K.J.; Gupta, A.; Merritt, F.S.; Oreglia, M.J.; Pilcher, J.E.; Spano, F.; Teuscher, R. [University of Chicago, Enrico Fermi Institute and Department of Physics, Chicago, IL (United States); Asai, S.; Ishii, K.; Kanzaki, J.; Kawagoe, K.; Kawamoto, T.; Kobayashi, T.; Komamiya, S.; Mashimo, T.; Mihara, S.; Mori, T.; Nakamura, I.; Nanjo, H.; Orito, S.; Saeki, T.; Toya, D.; Ueda, I.; Yamashita, S. [University of Tokyo, International Centre for Elementary Particle Physics and Department of Physics, Tokyo (Japan); Axen, D.; Lu, J.; McKenna, J. [University of British Columbia, Department of Physics, Vancouver, BC (Canada); Bailey, I.; Karlen, D.; Keeler, R.K.; McPherson, R.A.; Roney, J.M.; Sobie, R. [University of Victoria, Department of Physics, P.O.Box 3055, Victoria, BC (Canada); Barberio, E.; Burckhart, H.J.; De Roeck, A.; De Wolf, E.A.; Ferrari, P.; Frey, A.; Gruwe, M.; Hauschild, M.; Hawkings, R.; Meijers, F.; Oh, A.; Plane, D.E.; Przybycien, M.; Rabbertz, K. [and others
2006-08-15
Data from e{sup +}e{sup -} annihilation into hadrons at centre-of-mass energies between 91 GeV and 209 GeV collected with the OPAL detector at LEP, are used to study the four-jet rate as a function of the Durham algorithm resolution parameter y{sub cut}. The four-jet rate is compared to next-to-leading order calculations that include the resummation of large logarithms. The strong coupling measured from the four-jet rate is {alpha}{sub S(M{sub Z}{sub 0})}=0.1182{+-}0.0003(stat.){+-}0.0015(exp.) {+-}0.0011(had.){+-}0.0012(scale){+-}0.0013(mass), in agreement with the world average. Next-to-leading order fits to the D-parameter and thrust minor event-shape observables are also performed for the first time. We find consistent results, but with significantly larger theoretical uncertainties. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Klijnsma, Thomas; Dissertori, Guenther [ETH Zurich, Institute for Particle Physics, Zurich (Switzerland); Bethke, Siegfried [Max-Planck-Institute of Physics, Munich (Germany); Salam, Gavin P. [CERN, Theoretical Physics Department, Geneva (Switzerland); CNRS, UMR 7589, LPTHE, Paris (France)
2017-11-15
We present a determination of the strong coupling constant α{sub s} (m{sub Z}) using inclusive top-quark pair production cross section measurements performed at the LHC and at the Tevatron. Following a procedure first applied by the CMS Collaboration, we extract individual values of α{sub s} (m{sub Z}) from measurements by different experiments at several centre-of-mass energies, using QCD predictions complete in NNLO perturbation theory, supplemented with NNLL approximations to all orders, and suitable sets of parton distribution functions. The determinations are then combined using a likelihood-based approach, where special emphasis is put on a consistent treatment of theoretical uncertainties and of correlations between various sources of systematic uncertainties. Our final combined result is α{sub s} (m{sub Z}) = 0.1177{sup +0.0034}{sub -0.0036}. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Du, Jinjin; Li, Wenfang; Wen, Ruijuan; Li, Gang; Zhang, Pengfei; Zhang, Tiancai [State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan 030006 (China)
2013-08-19
We have experimentally demonstrated the strong coupling between single atoms and the higher-order Hermite-Gaussian transverse modes in a high-finesse optical microcavity. Compared to the usual low-order symmetric transverse modes, multiple lobes and the asymmetric spatial pattern of the titled modes provide more information about the motion of single atoms in the cavity. The motional information can be extracted from the measured transmission spectra, which includes the velocities and the positions of the atoms in vertical and off-axis directions. The scheme has great potential in time-resolved atom-cavity microscopy and in tracking the three-dimensional single atom trajectory in real time.
Energy Technology Data Exchange (ETDEWEB)
Li, Wenfang; Du, Jinjin; Wen, Ruijuan; Yang, Pengfei; Li, Gang; Zhang, Tiancai, E-mail: tczhang@sxu.edu.cn [State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan 030006 (China); Liang, Junjun [Department of Physics, Shanxi University, Taiyuan 030006 (China)
2014-03-17
We investigate the transmission of single-atom transits based on a strongly coupled cavity quantum electrodynamics system. By superposing the transit transmissions of a considerable number of atoms, we obtain the absorption spectra of the cavity induced by single atoms and obtain the temperature of the cold atom. The number of atoms passing through the microcavity for each release is also counted, and this number changes exponentially along with the atom temperature. Monte Carlo simulations agree closely with the experimental results, and the initial temperature of the cold atom is determined. Compared with the conventional time-of-flight (TOF) method, this approach avoids some uncertainties in the standard TOF and sheds new light on determining temperature of cold atoms by counting atoms individually in a confined space.
Dunaevskij, S M
2001-01-01
The calculation of the E(k) dispersion curves of the charge carriers in the LaMnO sub 3 -type perovskites for the basic types of the Mn sublattice squinted antiferromagnetic ordering is carried out within the frames of the strong coupling method. The calculation of the E(k) spectrum of the antiferromagnetic structures is accomplished for the first time with an account of the manganese e sub g -level degeneration and the Jahn-Teller distortion of the perovskite cubic structure, which required diagonalization of the eight order Hamiltonian matrices. The analytical expressions for the E(k) functions in the separate points and on the individual lines of the corresponding Brillouin zone are obtained. The accomplished calculations showed, that there can be no electron-hole symmetry of properties in the La sub 1 sub - sub x Ca sub x MnO sub 3 system
Energy Technology Data Exchange (ETDEWEB)
Andreev, V.; Belousov, A.; Fomenko, A.; Gogitidze, N.; Lebedev, A.; Malinovski, E.; Rusakov, S.; Vazdik, Y. [Lebedev Physical Institute, Moscow (Russian Federation); Baghdasaryan, A.; Zohrabyan, H. [Yerevan Physics Institute, Yerevan (Armenia); Begzsuren, K.; Ravdandorj, T.; Tseepeldorj, B. [Institute of Physics and Technology of the Mongolian Academy of Sciences, Ulaanbaatar (Mongolia); Belov, P.; Brinkmann, M.; Britzger, D.; Campbell, A.J.; Dodonov, V.; Eckerlin, G.; Elsen, E.; Fleischer, M.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Gouzevitch, M.; Haidt, D.; Kleinwort, C.; Krueger, K.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lobodzinski, B.; Meyer, A.B.; Meyer, J.; Niebuhr, C.; Olsson, J.E.; Ozerov, D.; Pahl, P.; Petrukhin, A.; Pirumov, H.; Pitzl, D.; Placakyte, R.; Radescu, V.; Schmitt, S.; Sefkow, F.; Shushkevich, S.; South, D.; Steder, M.; Wuensch, E. [DESY, Hamburg (Germany); Boudry, V.; Specka, A. [LLR, Ecole Polytechnique, CNRS/IN2P3, Palaiseau (France); Brandt, G. [Oxford University, Department of Physics, Oxford (United Kingdom); Brisson, V.; Jacquet, M.; Pascaud, C.; Zhang, Z.; Zomer, F. [LAL, Universite Paris-Sud, CNRS/IN2P3, Orsay (France); Buniatyan, A.; Newman, P.R.; Thompson, P.D. [University of Birmingham, School of Physics and Astronomy, Birmingham (United Kingdom); Bylinkin, A.; Bystritskaya, L.; Fedotov, A.; Rostovtsev, A. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Cantun Avila, K.B.; Contreras, J.G. [CINVESTAV, Departamento de Fisica Aplicada, Merida, Yucatan (Mexico); Ceccopieri, F.; Favart, L.; Grebenyuk, A.; Hreus, T.; Janssen, X.; Roosen, R.; Mechelen, P. van [Inter-University Institute for High Energies ULB-VUB, Brussels and Universiteit Antwerpen, Antwerp (Belgium); Cerny, K.; Pokorny, B.; Polifka, R.; Salek, D.; Valkarova, A.; Zacek, J.; Zlebcik, R. [Charles University, Faculty of Mathematics and Physics, Pragua (Czech Republic); Chekelian, V.; Grindhammer, G.; Kiesling, C. [Max-Planck-Institut fuer Physik, Munich (Germany); Dainton, J.B.; Gabathuler, E.; Greenshaw, T.; Klein, M.; Kostka, P.; Kretzschmar, J.; Laycock, P.; Maxfield, S.J.; Mehta, A.; Patel, G.D. [University of Liverpool, Department of Physics, Liverpool (United Kingdom); Daum, K.; Meyer, H. [Fachbereich C, Universitaet Wuppertal, Wuppertal (Germany); Diaconu, C.; Hoffmann, D.; Sauvan, E.; Vallee, C. [CPPM, Aix-Marseille University, CNRS/IN2P3, Marseille (France); Dobre, M.; Rotaru, M. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Dossanov, A. [Universitaet Hamburg, Institut fuer Experimentalphysik, Hamburg (Germany); Max-Planck-Institut fuer Physik, Munich (Germany); Egli, S.; Horisberger, R. [Paul Scherrer Institut, Villigen (Switzerland); Feltesse, J.; Perez, E.; Schoeffel, L. [CEA, DSM/Irfu, CE-Saclay, Gif-sur-Yvette (France); Ferencei, J. [Slovak Academy of Sciences, Institute of Experimental Physics, Kosice (Slovakia); Goerlich, L.; Mikocki, S.; Nowak, G.; Sopicki, P.; Turnau, J. [Institute for Nuclear Physics, Krakow (Poland); Grab, C. [Institut fuer Teilchenphysik, ETH, Zurich (Switzerland); Henderson, R.C.W. [University of Lancaster, Department of Physics, Lancaster (United Kingdom); Herbst, M.; Schultz-Coulon, H.C. [Universitaet Heidelberg, Kirchhoff-Institut fuer Physik, Heidelberg (Germany); Hladka, J.; Reimer, P. [Academy of Sciences of the Czech Republic, Institute of Physics, Prague (Czech Republic); Huber, F.; Sauter, M.; Schoening, A. [Universitaet Heidelberg, Physikalisches Institut, Heidelberg (Germany); Jung, H. [Inter-University Institute for High Energies ULB-VUB, Brussels and Universiteit Antwerpen, Antwerp (Belgium); DESY, Hamburg (Germany); Kapichine, M.; Morozov, A.; Spaskov, V. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Kogler, R. [Universitaet Hamburg, Institut fuer Experimentalphysik, Hamburg (Germany); Landon, M.P.J.; Rizvi, E.; Traynor, D. [Queen Mary, University of London, School of Physics and Astronomy, London (United Kingdom); Lange, W.; Naumann, T. [DESY, Zeuthen (Germany); Martyn, H.U. [I. Physikalisches Institut der RWTH, Aachen (Germany); Mueller, K.; Robmann, P.; Straumann, U.; Truoel, P. [Physik-Institut der Universitaet Zuerich, Zurich (Switzerland); Picuric, I.; Raicevic, N. [University of Montenegro, Faculty of Science, Podgorica (Montenegro); Sankey, D.P.C. [STFC, Rutherford Appleton Laboratory, Didcot, Oxfordshire (United Kingdom); Soloviev, Y. [DESY, Hamburg (Germany); Lebedev Physical Institute, Moscow (Russian Federation); Stella, B. [Universita di Roma Tre, Dipartimento di Fisica, Rome (Italy); INFN Roma 3 (Italy); Sykora, T. [Inter-University Institute for High Energies ULB-VUB, Brussels and Universiteit Antwerpen, Antwerp (Belgium); Charles University, Faculty of Mathematics and Physics, Pragua (Czech Republic); Tsakov, I. [Institute for Nuclear Research and Nuclear Energy, Sofia (Bulgaria); Wegener, D. [Institut fuer Physik, TU Dortmund, Dortmund (Germany); Collaboration: H1 Collaboration
2015-02-01
Inclusive jet, dijet and trijet differential cross sections aremeasured in neutral current deep-inelastic scattering for exchanged boson virtualities 150 < Q{sup 2} < 15 000 GeV{sup 2} using the H1 detector at HERA. The data were taken in the years 2003 to 2007 and correspond to an integrated luminosity of 351 pb{sup -1}. Double differential jet cross sections are obtained using a regularised unfolding procedure. They are presented as a function of Q{sup 2} and the transverse momentum of the jet, P{sub T}{sup jet}, and as a function of Q{sup 2} and the proton's longitudinal momentum fraction, ξ, carried by the parton participating in the hard interaction. In addition normalised double differential jet cross sections aremeasured as the ratio of the jet cross sections to the inclusive neutral current cross sections in the respective Q{sup 2} bins of the jet measurements. Compared to earlier work, the measurements benefit from an improved reconstruction and calibration of the hadronic final state. The cross sections are compared to perturbative QCD calculations in next-to-leading order and are used to determine the running coupling and the value of the strong coupling constant as α{sub s}(MZ) = 0.1165 (8){sub exp} (38){sub pdf,theo}. (orig.)
Lei, Yonggang
2017-05-23
It have been recognized that the coupling of graphene quantum dots (GQDs) with semiconductor photocatalysts endow the resulting nanocomposites with enhanced photocatalytic performances, however, the essential roles of GQDs have not been clearly revealed yet. Herein, we report that a high efficiency of the photocatalytic H2 evolution was achieved using strongly coupled nanohybrids of CdS with GQDs (CdS/GQDs) as visible-light-driven photocatalysts. CdS/GQDs nanohybrids were synthesized by a facile hydrothermal method in which the crystallization of CdS precursor and coupling of GQDs could be accomplished in one-step. GQDs are firmly decorated on the surface of CdS nanoparticles, forming “dot-on-particle” heterodimer structures. GQDs have no significant influence on the crystallite structure of CdS but render the nanohybrids with strong light absorption at the wavelength beyond the band edge of CdS. Under visible light irradiation (≥420nm), CdS/GQDs nanohybrids reach the highest H2 production rate of 95.4μmol·h−1, about 2.7 times higher than that of pure CdS nanoparticles, at GQDs content of 1.0wt %, and the apparent quantum efficiency (AQE) was determined to be 4.2% at 420nm. Incident light-wavelength dependent experiments reveal that the light absorption of CdS dominated the performance of nanohybrids, and the excess light absorption coming from GQDs hardly contributes to the observed higher activity. Photocurrent response, steady-state and time-resolved PL, and EIS measurements suggest that the high activity of CdS/GQDs is attributed predominantly to the graphene-like nature of GQDs, which can act as an efficient electron acceptor to induce an efficient charge separation. This work clearly reveals that GQDs mainly played a role of electron acceptor instead of a photosensitizer in enhancing the photocatalytic H2 evolution performances of CdS/GQDs nanohybrids, which offers a new insight to understand the essential roles of GQDs in semiconductor
The Bright Fluorescent Protein mNeonGreen Facilitates Protein Expression Analysis In Vivo
Directory of Open Access Journals (Sweden)
Lola Hostettler
2017-02-01
Full Text Available The Green Fluorescent Protein (GFP has been tremendously useful in investigating cell architecture, protein localization, and protein function. Recent developments in transgenesis and genome editing methods now enable working with fewer transgene copies and, consequently, with physiological expression levels. However, lower signal intensity might become a limiting factor. The recently developed mNeonGreen protein is a brighter alternative to GFP in vitro. The goal of the present study was to determine how mNeonGreen performs in vivo in Caenorhabditis elegans—a model used extensively for fluorescence imaging in intact animals. We started with a side-by-side comparison between cytoplasmic forms of mNeonGreen and GFP expressed in the intestine, and in different neurons, of adult animals. While both proteins had similar photostability, mNeonGreen was systematically 3–5 times brighter than GFP. mNeonGreen was also used successfully to trace endogenous proteins, and label specific subcellular compartments such as the nucleus or the plasma membrane. To further demonstrate the utility of mNeonGreen, we tested transcriptional reporters for nine genes with unknown expression patterns. While mNeonGreen and GFP reporters gave overall similar expression patterns, low expression tissues were detected only with mNeonGreen. As a whole, our work establishes mNeonGreen as a brighter alternative to GFP for in vivo imaging in a multicellular organism. Furthermore, the present research illustrates the utility of mNeonGreen to tag proteins, mark subcellular regions, and describe new expression patterns, particularly in tissues with low expression.
Study of adsorption of Neon on open Carbon nanohorns aggregates
Ziegler, Carl Andrew
Adsorption isotherms can be used to determine surface area of a substrate and the heat released when adsorption occurs. Our measurements are done determining the equilibrium pressures corresponding to a given amount of gas adsorbed on a substrate at constant temperature. The adsorption studies were done on aggregates of open dahlia-like carbon nanohorns. The nanohorns were oxidized for 9 hours at 550 °C to open them up and render their interior space accessible for adsorption. Volumetric adsorption measurements of Ne were performed at twelve different temperatures between 19 K and 48 K. The isotherms showed two substeps. The first substep corresponds to adsorption on the high energy binding sites in the interior of the nanohorns, near the tip. The second substep corresponds to low energy binding sites both on the outside of the nanotubes and inside the nanotube away from the tip. The isosteric heat measurements obtained from the isotherm data also shows these two distinct substeps. The effective surface area of the open nanotubes was determined from the isotherms using the point-B method. The isosteric heat and surface area data for neon on open nanohorns were compared to two similar experiments of neon adsorbed on aggregates of closed nanohorns.
Electron scattering from neon via effective range theory
Energy Technology Data Exchange (ETDEWEB)
Fedus, Kamil, E-mail: kamil@fizyka.umk.pl [Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Torun (Poland)
2014-07-01
Elastic cross-sections for electron scattering on neon from 0 energy up to 16 eV are analyzed by an analytical approach to the modified effective range theory (MERT). It is shown that energy and angular variations of elastic differential, integral and momentum transfer cross sections can be accurately parameterized by six MERT coefficients up to the energy threshold for the first Feshbach resonance. MERT parameters are determined empirically by numerical comparison with large collection of available experimental data of elastic total (integral) cross-sections. The present analysis is validated against numerous electron beams and swarm experiments. The comparison of derived MERT parameters with those found for other noble gases, helium, argon and krypton, is done. The derived scattering length (for the s-partial wave) in neon, 0.227a0, agrees well with recent theories; it is small but, differently from Ar and Kr, still positive. Analogue parameters for the p-wave and the d-wave are negative and positive respectively for all the four gases compared. (author)
Yu, B.; van Ingen, H.|info:eu-repo/dai/nl/297054651; Freedberg, D.I.
2013-01-01
Strong (1)H-(1)H coupling can significantly reduce the accuracy of (1)J(CH) measured from frequency differences in coupled HSQC spectra. Although accurate (1)J(CH) values can be extracted from spectral simulation, it would be more convenient if the same accurate (1)J(CH) values can be obtained
Usman, Muhammad
2015-10-21
Strongly-coupled quantum dot molecules (QDMs) are widely employed in the design of a variety of optoelectronic, photovoltaic, and quantum information devices. An efficient and optimized performance of these devices demands engineering of the electronic and optical properties of the underlying QDMs. The application of electric fields offers a way to realise such a control over the QDM characteristics for a desired device operation. We performed multi-million-atom atomistic tight-binding calculations to study the influence of electric fields on the electron and hole wave function confinements and symmetries, the ground-state transition energies, the band-gap wavelengths, and the optical transition modes. Electrical fields parallel (Ep) and anti-parallel (Ea) to the growth direction were investigated to provide a comprehensive guide for understanding the electric field effects. The strain-induced asymmetry of the hybridized electron states is found to be weak and can be balanced by applying a small Ea electric field, of the order of 1 kV cm(-1). The strong interdot couplings completely break down at large electric fields, leading to single QD states confined at the opposite edges of the QDM. This mimics a transformation from a type-I band structure to a type-II band structure for the QDMs, which is a critical requirement for the design of intermediate-band solar cells (IBSCs). The analysis of the field-dependent ground-state transition energies reveals that the QDM can be operated both as a high dipole moment device by applying large electric fields and as a high polarizability device under the application of small electric field magnitudes. The quantum confined Stark effect (QCSE) red shifts the band-gap wavelength to 1.3 μm at the 15 kV cm(-1) electric field; however the reduced electron-hole wave function overlaps lead to a decrease in the interband optical transition strengths by roughly three orders of magnitude. The study of the polarisation-resolved optical
Alpha and beta particle induced scintillations in liquid and solid neon
Michniak, R A; McKinsey, D N; Doyle, J M
2002-01-01
Scintillations induced by alpha and beta particles in liquid and solid neon are studied and their light yield measured. Charged particle scintillation in neon is primarily in the extreme ultraviolet (EUV). We detect this EUV light by converting it to blue using a wavelength shifting fluor and detecting the blue light with a photomultiplier tube. It is observed that liquid neon is a somewhat less-efficient scintillator than liquid helium for both alpha and beta radiation while the light yield in solid neon is greater than in liquid helium. Based on our measurements of the relative light yields of liquid and solid neon to liquid helium whose absolute light yield has previously been determined, we find that an alpha source in liquid neon produces up to 5900 photons per MeV while a beta source produces up to 7400 photons per MeV. In solid neon, we find that an alpha particle produces up to 9300 photons per MeV while a beta particle produces up to 17,000 photons per MeV. We observe a significant dependence of the ...
Isotopic effects in the neon fixed point: uncertainty of the calibration data correction
Steur, Peter P. M.; Pavese, Franco; Fellmuth, Bernd; Hermier, Yves; Hill, Kenneth D.; Seog Kim, Jin; Lipinski, Leszek; Nagao, Keisuke; Nakano, Tohru; Peruzzi, Andrea; Sparasci, Fernando; Szmyrka-Grzebyk, Anna; Tamura, Osamu; Tew, Weston L.; Valkiers, Staf; van Geel, Jan
2015-02-01
The neon triple point is one of the defining fixed points of the International Temperature Scale of 1990 (ITS-90). Although recognizing that natural neon is a mixture of isotopes, the ITS-90 definition only states that the neon should be of ‘natural isotopic composition’, without any further requirements. A preliminary study in 2005 indicated that most of the observed variability in the realized neon triple point temperatures within a range of about 0.5 mK can be attributed to the variability in isotopic composition among different samples of ‘natural’ neon. Based on the results of an International Project (EUROMET Project No. 770), the Consultative Committee for Thermometry decided to improve the realization of the neon fixed point by assigning the ITS-90 temperature value 24.5561 K to neon with the isotopic composition recommended by IUPAC, accompanied by a quadratic equation to take the deviations from the reference composition into account. In this paper, the uncertainties of the equation are discussed and an uncertainty budget is presented. The resulting standard uncertainty due to the isotopic effect (k = 1) after correction of the calibration data is reduced to (4 to 40) μK when using neon of ‘natural’ isotopic composition or to 30 μK when using 20Ne. For comparison, an uncertainty component of 0.15 mK should be included in the uncertainty budget for the neon triple point if the isotopic composition is unknown, i.e. whenever the correction cannot be applied.
International Nuclear Information System (INIS)
Mohammadi, M A; Verma, R; Sobhanian, S; Wong, C S; Lee, S; Springham, S V; Tan, T L; Lee, P; Rawat, R S
2007-01-01
The UNU-ICTP plasma focus with a significantly longer than conventional anode can still be a reasonably good neon soft x-ray (SXR) source. The highest average neon SXR yield of 3.3 J was achieved at 3 mbar. The time difference between the two first peaks of the voltage probe signal at the radial collapse phase was found to be inversely related to the SXR yield, i.e. the smaller the time difference, the higher the yield and vice versa. The estimation of average current sheath speeds using the shadowgraphic method coupled with laser and focus peak timing signals showed that the average axial rundown speed is similar to the one obtained for the optimal anode length but the average radial compression speed is decreased significantly. The range of pressure for a good neon SXR yield, however, has become much narrower, making efficient plasma focus operation a very sensitive function of the filling gas pressure for longer than the optimal anode length
Energy Technology Data Exchange (ETDEWEB)
Aktas, A. [DESY, Hamburg (Germany); Alexa, C. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Andreev, V. [Lebedev Physical Institute, Moscow (RU)] (and others)
2007-05-15
Inclusive jet production is studied in neutral current deep-inelastic positron-proton scattering at large four momentum transfer squared Q{sup 2} > 150 GeV{sup 2} with the H1 detector at HERA. Single and double differential inclusive jet cross sections are measured as a function of Q{sup 2} and of the transverse energy E{sub T} of the jets in the Breit frame. The measurements are found to be well described by calculations at next-to-leading order in perturbative QCD. The running of the strong coupling is demonstrated and the value of {alpha}{sub s}(M{sub Z}) is determined. The ratio of the inclusive jet cross section to the inclusive neutral current cross section is also measured and used to extract a precise value for {alpha}{sub s}(M{sub Z})=0.1193{+-}0.0014(exp.){sup +0.0047}{sub -0.0030}(th.){+-}0.0016(pdf). (orig.)
International Nuclear Information System (INIS)
Martirena, S.G.
1994-04-01
In this work, a measurement of the strong coupling constant α s in e + e - annihilation at a center-of-mass energy of 91.6 GeV is presented. The measurement was performed with the SLD at the Stanford Linear Collider facility located at the Stanford Linear Accelerator Center in California. The procedure used consisted of measuring the rate of hard gluon radiation from the primary quarks in a sample of 9,878 hadronic events. After defining the asymptotic manifestation of partons as 'jets', various phenomenological models were used to correct for the hadronization process. A value for the QCD scale parameter Λ bar MS , defined in the bar MS renormalization convention with 5 active quark flavors, was then obtained by a direct fit to O(α s 2 ) calculations. The value of α s obtained was α s (M z0 ) = 0.122 ± 0.004 -0.007 +0.008 where the uncertainties are experimental (combined statistical and systematic) and theoretical (systematic) respectively. Equivalently, Λ bar MS = 0.28 -0.10 +0.16 GeV where the experimental and theoretical uncertainties have been combined
Huang, Haoliang; Huang, Junying; Liu, Weipeng; Fang, Yueping; Liu, Yingju
2017-11-15
As one of the most promising Pt alternatives for cost-effective hydrogen production, molybdenum disulfide (MoS 2 ), although has been studied extensively to improve its electrocatalytic activity, suffers from scarce active sites, low conductivity, and lack of interaction with substrates. To this end, we anchor ultradispersed and single-layered MoS 2 nanoflakes on graphene sheets via a hybrid intermediate (MoO x -cysteine-graphene oxide), which not only confines the subsequent growth of MoS 2 on the graphene surface but also ensures the intimate interaction between Mo species and graphene at the initial stage. Mo-O-C bond and a possible residual MoO 3-x layer are proposed to comprise the interface bridging the two inherent incompatible phases, MoS 2 and graphene. This strongly coupled structure together with the highly exposed MoS 2 morphology accelerates the electron injection from graphene to the active sites of MoS 2 , and thus the hydrogen evolution reaction (HER) can achieve an overpotential of ∼275 mV at ∼-740 mA cm -2 , and a Pt-like Tafel slope of ∼35 mV dec -1 . Our results shed light on the indispensable role of interfacial interaction within semiconducting material-nanocarbon composites and provide a new insight into the actual activity of MoS 2 toward the HER.
CMS Collaboration
2017-01-01
A measurement of inclusive multijet event cross sections is presented from proton-proton collisions recorded at $\\sqrt{s} = 8\\,$TeV with the CMS detector and corresponding to an integrated luminosity of $19.7\\,\\mathrm{fb}^{-1}$. Jets are reconstructed with the anti-k$_t$ clustering algorithm for a jet size parameter $R=0.7$ in a phase space region ranging up to jet transverse momenta $p_\\mathrm{T}$ of $2.0\\,$TeV and an absolute rapidity of $|y|=2.5$. The inclusive 2-jet and 3-jet event cross sections are measured as a function of the average $p_\\mathrm{T}$ of the two leading jets. The data are well described by predictions at next-to-leading order in perturbative quantum chromodynamics and additionally are compared to several Monte Carlo event generators. The strong coupling constant at the scale of the Z boson mass is inferred from a fit of the ratio of the 3-jet over 2-jet event cross section giving $\\alpha_s(M_Z) = 0.1150\\,\\pm0.0010\\,\\textrm{(exp)}\\,\\pm0.0013\\,\\textrm{(PDF)}\\, \\pm0.0015\\,\\textrm{(NP)}\\,^{+...
Dirks, Andreas; Mikelsons, Karlis; Krishnamurthy, H R; Freericks, James K
2014-02-01
We present a nonequilibrium strong-coupling approach to inhomogeneous systems of ultracold atoms in optical lattices. We demonstrate its application to the Mott-insulating phase of a two-dimensional Fermi-Hubbard model in the presence of a trap potential. Since the theory is formulated self-consistently, the numerical implementation relies on a massively parallel evaluation of the self-energy and the Green's function at each lattice site, employing thousands of CPUs. While the computation of the self-energy is straightforward to parallelize, the evaluation of the Green's function requires the inversion of a large sparse 10(d) × 10(d) matrix, with d > 6. As a crucial ingredient, our solution heavily relies on the smallness of the hopping as compared to the interaction strength and yields a widely scalable realization of a rapidly converging iterative algorithm which evaluates all elements of the Green's function. Results are validated by comparing with the homogeneous case via the local-density approximation. These calculations also show that the local-density approximation is valid in nonequilibrium setups without mass transport.
Tahir, N A; Shutov, A; Varentsov, D; Udrea, S; Hoffmann, Dieter H H; Juranek, H; Redmer, R; Portugues, R F; Lomonosov, I V; Fortov, V E
2003-01-01
Intense heavy ion beams deposit energy very efficiently over extended volumes of solid density targets, thereby creating large samples of strongly coupled plasmas. Intense beams of energetic heavy ions are therefore an ideal tool to research this interesting field. It is also possible to design experiments using special beam-target geometries to achieve low-entropy compression of samples of matter. This type of experiments is of particular interest for studying the problem of hydrogen metallization. In this paper we present a design study of such a proposed experiment that will be carried out at the future heavy ion synchrotron facility SIS100, at the Gesellschaft fuer Schwerionenforschung, Darmstadt. This study has been done using a two-dimensional hydrodynamic computer code. The target consists of a solid hydrogen cylinder that is enclosed in a thick shell of lead whose one face is irradiated with an ion beam which has an annular (ring shaped) focal spot. The beam intensity and other parameters are consider...
Energy Technology Data Exchange (ETDEWEB)
Faria da Veiga, Paulo A., E-mail: veiga@icmc.usp.br; O’Carroll, Michael, E-mail: michaelocarroll@gmail.com; Valencia Alvites, José C., E-mail: cien.mat@hotmail.com [Departamento de Matemática Aplicada e Estatística, ICMC, USP-São Carlos, C.P. 668, São Carlos, SP 13560-970 (Brazil)
2016-03-15
Considering a 3 + 1 dimensional lattice quantum chromodynamics (QCD) model defined with the improved Wilson action, three flavors, and 4 × 4 Dirac spin matrices, in the strong coupling regime, we reanalyze the question of the existence of the eightfold way baryons and complete our previous work where the existence of isospin octet baryons was rigorously solved. Here, we show the existence of isospin decuplet baryons which are associated with isolated dispersion curves in the subspace of the underlying quantum mechanical Hilbert space with vectors constructed with an odd number of fermion and antifermion basic quark and antiquark fields. Moreover, smoothness properties for these curves are obtained. The present work deals with a case for which the traditional method to solve the implicit equation for the dispersion curves, based on the use of the analytic implicit function theorem, cannot be applied. We do not have only one but two solutions for each one-baryon decuplet sector with fixed spin third component. Instead, we apply the Weierstrass preparation theorem, which also provides a general method for the general degenerate case. This work is completed by analyzing a spectral representation for the two-baryon correlations and providing the leading behaviors of the field strength normalization and the mass of the spectral contributions with more than one-particle. These are needed results for a rigorous analysis of the two-baryon and meson-baryon particle spectra.
The infrared spectrum of HOOH+ trapped in solid neon.
Thompson, Warren E; Lugez, Catherine L; Jacox, Marilyn E
2012-10-14
When a Ne:H(2)O(2) mixture is codeposited at 4.3 K with a beam of neon atoms that have been excited in a microwave discharge, three new, photosensitive absorptions appear which can be assigned to the three infrared-active vibrational fundamentals of trans-HOOH(+). When the Ne:H(2)O(2) deposition system is pretreated with the vapors of D(2)O, the product absorptions include new peaks which can be attributed to vibrational fundamentals of trans-HOOD(+) and trans-DOOD(+). Density functional calculations of the vibrational fundamentals of the three hydrogen peroxide cation isotopologues support the proposed assignments. Broad, photosensitive product absorptions also appear near the positions of vibrational transitions of O(3)(-), and may be contributed by a weakly bound complex of that species with H(2)O.
Recent results from neutrino interactions in heavy neon
International Nuclear Information System (INIS)
Baltay, C.; Caroumbalis, D.; French, H.
1978-01-01
We report recent results from an analysis of 100,000 pictures from the Fermilab 15 ft. bubble chamber filled with heavy neon and exposed to the double horn focused, wideband ν/sub μ/ beam. We have found 164 dilepton (μ - e + ) events with 33 vees, in good agreement with the GIM model of charm production. We have also observed the production of the charmed D 0 meson, followed by the decay D 0 → K 0 π + π - , at a rate of (0.7 +- 0.2)% of all charged current events. We have carried out searches for charm changing neutral current processes and for heavy lepton production, both with negative results; the upper limits obtained in these searches are given
Color Appearance of the Neon Color Spreading Effect
Directory of Open Access Journals (Sweden)
Damir Vusić
2017-04-01
Full Text Available As a part of this paper, the influence of various parameters within the target process of graphic reproduction on the color appearance of the neon color spreading effect was investigated. The shift in a color appearance qualitatively is determined through the calculation of changes in perceptual attributes of color, i.e. differences in lightness, chroma and hue. The influence of different media (printed images, and LCD display in the “cross-media” system was examined, as well as the role of the inserted segment color choice and background of the primary stimulus as an element of design solutions. These parameters were evaluated in a variety of ambient conditions and under the observation of three CIE standard light sources and illuminants. It was found that it was mostly the changes of the chroma and lightness. The change in the color hue is the lowest.
Green's function calculation of the satellite spectrum of neon
International Nuclear Information System (INIS)
Kheifets, A.S.
1995-01-01
The single-hole Green's function with the lowest-order self-energy part has been used to calculate energies and spectroscopic factors of the neon ion ground and excited states which originated from the removal of the 2s and 2p valence electrons. The simplest two-hole-one-electron ion sates were included explicitly to the self-energy. More complex (m+l)-hole-m-electron states were treated implicitly by using the experimental energy of the two holes in the simplest ion states. The results of the calculation are found to be consistent with experimental satellite line positions and intensities obtained from recent photoionization and electron impact ionization measurements. 20 refs., 5 tabs
NEON's Mobile Deployment Platform: A Resource for Community Research
Sanclements, M.
2015-12-01
Here we provide an update on construction and validation of the NEON Mobile Deployment Platforms (MDPs) as well as a description of the infrastructure and sensors available to researchers in the future. The MDPs will provide the means to observe stochastic or spatially important events, gradients, or quantities that cannot be reliably observed using fixed location sampling (e.g. fires and floods). Due to the transient temporal and spatial nature of such events, the MDPs will be designed to accommodate rapid deployment for time periods up to ~ 1 year. Broadly, the MDPs will be comprised of infrastructure and instrumentation capable of functioning individually or in conjunction with one another to support observations of ecological change, as well as education, training and outreach.
Emissivity of the pulsed capacitive discharge in helium-iodine and neon-iodine mixtures
Shuaibov, A. K.; Minya, A. I.; Gomoki, Z. T.; Laslov, G. E.
2009-01-01
The emission parameters of a pulsed capacitive discharge initiated in helium-iodine and neon-iodine mixtures are reported. The discharge plasma emits at wavelengths of 183.0 and 206.2 nm, which correspond to iodine atom spectral lines. The capacitive discharge is initiated in a cylindrical quartz tube with an electrode distance of 10 cm. The discharge radiation is optimized in exciting pulse repetition rate and helium and neon pressures in He(Ne)-I2 mixtures. The optimal pressures of helium, neon, and iodine vapor fall into the ranges 0.8-2.0 kPa, 0.5-1.0 Pa, and ≤60 Pa, respectively.
Energy Technology Data Exchange (ETDEWEB)
Britzger, Daniel Andreas
2013-10-15
In this thesis double-differential cross sections for jet production in neutral current deep-inelastic e{sup {+-}}p scattering (DIS) are presented at the center-of-mass energy of {radical}(s)=319 GeV, and in the kinematic range of the squared four-momentum transfer 150< Q{sup 2}<15 000 GeV{sup 2} and the inelasticity 0.2
Fully differential single-photon double ionization of neon and argon
Yip, Frank; Martin, Fernando; Rescigno, Thomas; McCurdy, C.
2013-05-01
Double photoionization of neon and argon differ significantly from helium in that three different final state couplings of the residual double ion (1 S , 1 D , and 3 P) are possible and greatly impact the observed angular distributions, but the multi-electron nature of such targets makes ab initio theoretical treatments of this correlated process a challenge. Triply differential cross sections (TDCS) have been calculated for single photon double ionization of these heavier rare gases at various photon energies by utilizing an expanded frozen-core treatment to represent the remaining N - 2 target electrons of the residual ion. The resulting angular distributions are compared with and show significant agreement with existing experimental data. Work supported by U. S. Dept. of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences Contract DE-AC02-05CH11231, by the MICINN Projects No. FIS2010-15127, No. ACI2008-0777,No. CSD 2007-00010, and ERC Advanced Grant 290853.
Lu, Hua-Jie; Chen, Xin-Jun; Ma, Jin
2014-08-01
Statolith is one of the most important hard tissues of cephalopods which is widely used in the research of fisheries ecology including population structure, life history reconstruction and so on. Trace elements of 18 statoliths of neon flying squid Ommastrephes bartramii collected in the Northwest Pacific Ocean in 2007 by Chinese jigging fishing fleets were analyzed by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The results indicated that the statoliths of O. bartramii mainly contained 55 elements, and calcium (Ca), strontium (Sr), sodium (Na), phosphorus (P), potassium (K), silicon (Si), magnesium (Mg), boron (B), iron (Fe), barium (Ba) were the 10 most abundant elements. The analysis of variance showed that there was no significant difference in each element distribution between different sexual squid except for P, Si and B. Significant differences existed in the contents of Sr and Na but no significant difference was found in the contents of Ca, P, K, Si, Mg, B, Fe and Ba between different hatching populations. There were significant differences in the contents of Ca, Sr, Na, P, Mg and Ba, but no significant difference was found in the contents of K, Fe, B and Si in the statoliths among different growth zones. This study presented Sr and Na could be the best two trace elements used in the research on the population structure and life history reconstruction for O. bartramii.
Kolacsek, Orsolya; Erdei, Zsuzsa; Apáti, Ágota; Sándor, Sára; Izsvák, Zsuzsanna; Ivics, Zoltán; Sarkadi, Balázs
2014-01-01
Abstract The Sleeping Beauty (SB) and piggyBac (PB) DNA transposons represent an emerging new gene delivery technology, potentially suitable for human gene therapy applications. Previous studies pointed to important differences between these transposon systems, depending on the cell types examined and the methodologies applied. However, efficiencies cannot always be compared because of differences in applications. In addition, “overproduction inhibition,” a phenomenon believed to be a characteristic of DNA transposons, can remarkably reduce the overall transgenic rate, emphasizing the importance of transposase dose applied. Therefore, because of lack of comprehensive analysis, researchers are forced to optimize the technology for their own “in-house” platforms. In this study, we investigated the transposition of several SB (SB11, SB32, SB100X) and PB (mPB and hyPB) variants in various cell types at three levels: comparing the excision efficiency of the reaction by real-time PCR, testing the overall transgenic rate by detecting cells with stable integrations, and determining the average copy number when using different transposon systems and conditions. We concluded that high excision activity is not always followed by a higher transgenic rate, as exemplified by the hyperactive transposases, indicating that the excision and the integration steps of transposition are not strongly coupled as previously thought. In general, all levels of transposition show remarkable differences depending on the transposase used and cell lines examined, being the least efficient in human embryonic stem cells (hESCs). In spite of the comparably low activity in those special cell types, the hyperactive SB100X and hyPB systems could be used in hESCs with similar transgenic efficiency and with reasonably low (2–3) transgene copy numbers, indicating their potential applicability for gene therapy purposes in the future. PMID:25045962
Energy Technology Data Exchange (ETDEWEB)
Tahir, N A [Institut fuer Theoretische Physik, Universitaet Frankfurt, Postfach 11 19 32, 60054 Frankfurt (Germany); Piriz, A R [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Shutov, A [Institute for Problems in Chemical Physics Research, Chernogolovka, Russia (Russian Federation); Varentsov, D [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgarten Str. 9, 64289 Darmstadt (Germany); Udrea, S [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgarten Str. 9, 64289 Darmstadt (Germany); Hoffmann, D H H [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgarten Str. 9, 64289 Darmstadt (Germany); Juranek, H [Fachbereich Physik, Universitaet Rostock, 18051 Rostock (Germany); Redmer, R [Fachbereich Physik, Universitaet Rostock, 18051 Rostock (Germany); Portugues, R F [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Lomonosov, I [Institute for Problems in Chemical Physics Research, Chernogolovka, Russia (Russian Federation); Fortov, V E [Institute for Problems in Chemical Physics Research, Chernogolovka, Russia (Russian Federation)
2003-06-06
Intense heavy ion beams deposit energy very efficiently over extended volumes of solid density targets, thereby creating large samples of strongly coupled plasmas. Intense beams of energetic heavy ions are therefore an ideal tool to research this interesting field. It is also possible to design experiments using special beam-target geometries to achieve low-entropy compression of samples of matter. This type of experiments is of particular interest for studying the problem of hydrogen metallization. In this paper we present a design study of such a proposed experiment that will be carried out at the future heavy ion synchrotron facility SIS100, at the Gesellschaft fuer Schwerionenforschung, Darmstadt. This study has been done using a two-dimensional hydrodynamic computer code. The target consists of a solid hydrogen cylinder that is enclosed in a thick shell of lead whose one face is irradiated with an ion beam which has an annular (ring shaped) focal spot. The beam intensity and other parameters are considered to be the same as expected at the future SIS100 facility. The simulations show that due to multiple shock reflection between the cylinder axis and the lead-hydrogen boundary, one can achieve up to 20 times solid density in hydrogen while keeping the temperature as low as a few thousand K. The corresponding pressure is of the order of 10 Mbar. These values of the physical parameters lie within the range of theoretically predicted values for hydrogen metallization. We have also carried out a parameter study of this problem by varying the target and beam parameters over a wide range. It has been found that the results are very insensitive to such changes in the input parameters.
International Nuclear Information System (INIS)
Dai, Yang; Borisov, Alexey B.; Boyer, Keith; Rhodes, Charles K.
2000-01-01
The construction of inverse states in a finite field F P α enables the organization of the mass scale with fundamental octets in an eight-dimensional index space that identifies particle states with residue class designations. Conformance with both CPT invariance and the concept of supersymmetry follows as a direct consequence of this formulation. Based on two parameters (P α and g α ) that are anchored on a concordance of physical data, this treatment leads to (1) a prospective mass for the muon neutrino of approximately27.68 meV, (2) a value of the unified strong-electroweak coupling constant α* = (34.26) -1 that is physically defined by the ratio of the electron neutrino and muon neutrino masses, and (3) a see-saw congruence connecting the Higgs, the electron neutrino, and the muon neutrino masses. Specific evaluation of the masses of the corresponding supersymmetric Higgs pair reveals that both particles are superheavy (> 10 18 GeV). No renormalization of the Higgs masses is introduced, since the calculational procedure yielding their magnitudes is intrinsically divergence-free. Further, the Higgs fulfills its conjectured role through the see-saw relation as the particle defining the origin of all particle masses, since the electron and muon neutrino systems, together with their supersymmetric partners, are the generators of the mass scale and establish the corresponding index space. Finally, since the computation of the Higgs masses is entirely determined by the modulus of the field P α , which is fully defined by the large-scale parameters of the universe through the value of the universal gravitational constant G and the requirement for perfect flatness (Omega = 1.0), the see-saw congruence fuses the concepts of mass and space and creates a new unified archetype
Fragmentation dynamics of ionized neon trimer inside helium nanodroplets: a theoretical study.
Bonhommeau, David; Viel, Alexandra; Halberstadt, Nadine
2004-06-22
We report a theoretical study of the fragmentation dynamics of Ne(3) (+) inside helium nanodroplets, following vertical ionization of the neutral neon trimer. The motion of the neon atoms is treated classically, while transitions between the electronic states of the ionic cluster are treated quantum mechanically. A diatomics-in-molecules description of the potential energy surfaces is used, in a minimal basis set consisting of three effective p orbitals on each neon atom for the missing electron. The helium environment is modeled by a friction force acting on the neon atoms when their speed exceeds the Landau velocity. A reasonable range of values for the corresponding friction coefficient is obtained by comparison with existing experimental measurements. (c) 2004 American Institute of Physics.
Development of a sodium-pump/neon-lasant photopumped soft X-ray laser
International Nuclear Information System (INIS)
Stephanakis, S.J.; Apruzese, J.P.; Burkhalter, P.G.
1988-01-01
Resonant photopumping of heliumlike neon by heliumlike sodium is investigated to extend this potentially efficient technique for inversion and lasing to shorter wavelengths. Properties of the sodium-pump plasma and the neon-lasant plasma required to optimize fluorescence and lasing are determined. The implosion of a sodium-bearing plasma with a megampere pulsed-power driver (Gamble II) is used to produce a linear Z-pinch with up to 25 GW of sodium-pump-line radiation. A separate neon plasma, driven by part of the return current form the imploding sodium plasma, is created parallel to the sodium line source at a distance of 5 cm. Implosion requirements for the neon plasma and its dynamics in the Gamble II return-current geometry are described. Evidence for population inversion is indicated by fluorescence enhancement of the 11-A resonance line from the n = 4 level of neon when pumped by sodium. The neon spectra are in qualitative agreement with calculations based on the sodium-pump power. Improvements in the experiment required to achieve lasing are discussed
Directory of Open Access Journals (Sweden)
Ivanova-Stanik Irena
2017-03-01
Full Text Available Numerical simulations with the COREDIV code of JET H-mode discharges with 25 MW of auxiliary heating in the ITER-like wall (ILW configuration with different impurity seedings – nitrogen (N, neon (Ne, argon (Ar and krypton (Kr – are presented. All simulations have been performed with the same transport model and input discharge parameters like auxiliary heating, volume average plasma density, confinement factor. Only the seeded impurity puff rate was changed in the calculations. It appears that for the considered heating power of 25 MW and relatively low volume electron average density = 6.2 × 1019 m−3, impurity seeding is necessary. It has been found that for every gas at the maximum level of the seeding rate, allowed by the code convergence, the power to the plate is reduced up to 2–4 MW, with electron temperature at the plate of about 2 eV, indicating semi-detached conditions in the divertor region. It should be noted, however, that in cases with low and medium Z impurity (N, Ne and Ar, tungsten radiation is a significant part of radiation losses and stays above 22–32% of the total energy losses, but for high Z impurity (Kr it is reduced up to 10% of the total losses. The maximum of the Kr radiation is between the pedestal region and separatrix, showing that radiative mantle can be created, which might have a strong influence on the plasma parameters in the pedestal region.
Energy Technology Data Exchange (ETDEWEB)
Astruc, J.M. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires
1967-12-01
In the first part, free-convection and nucleate pool boiling heat transfer (up to burn-out heat flux) between a platinum wire of 0.15 mm in diameter in neon, deuterium and hydrogen has been studied at atmospheric pressure. These measurements were continued in liquid neon up to 23 bars (Pc {approx_equal} 26.8 b). Film boiling heat transfer coefficients have been measured in pool boiling liquid neon at atmospheric pressure with three heating wires (diameters 0.2, 0.5, 2 mm). All the results have been compared with existing correlations. The second part is devoted to measurements of the critical heat flux limiting heat transfer with small temperature differences between the wall and the liquid neon flowing inside a tube (diameters 3 x 3.5 mm) heated by joule effect on 30 cm of length. Influences of flow stability, nature of electrical current, pressure, mass flow rate and subcooling are shown. In conclusion, the similarity of the heat transfer characteristics in pool boiling as well as in forced convection of liquid neon and hydrogen is emphasized. (author) [French] Dans la premiere partie, on a etudie les echanges thermiques en regime de convection libre et d'ebullition nucleee (jusqu'au flux critique de l'ebullition nucleee) entre un fil de platine (diametre 0,15 mm) chauffe electriquement et un bain de liquide (neon, deuterium, ou hydrogene) bouillant a la pression atmospherique. On a poursuivi ces mesures dans le neon jusqu'a une pression de 23 bars (Pc {approx_equal} 26,8 b). On a mesure en outre les coefficients d'echanges thermiques en regime de calefaction dans le neon liquide a pression atmospherique. Tous ces resultats sont compares a diverses correlations existantes. La deuxieme partie est axee sur la mesure des flux de chaleur critiques limitant les echanges thermiques avec faible ecart de temperatures entre la paroi et le neon liquide s'ecoulant dans un tube (diam. 3 x 3,5 mm) chauffe par effet joule sur 30 cm de longueur. On
Strange particle production in neutrino-neon charged current interactions
International Nuclear Information System (INIS)
Plano, R.; Baker, N.J.; Connolly, P.L.
1986-01-01
Neutral strange particle production in charged-current muon-neutrino interactions have been studied in the Fermilab 15-foot neon bubble chamber. Associated production is expected to be the major source of strange particles in charged-current neutrino interactions. σ-neutral and ξ-minus production by neutrinos was observed. The dependence on various leptonic and hadronic variables is investigated. A fit to single and associated production of s, s/anti-s, and c quarks is described based on the number of single and double strange particle production events. Inclusive neutral strange particle decays (V 0 ) production rates as a fraction of all charged-current events are measured and are tabulated. The λ/K ratio is found to be 0.39 +- 0.04 and the fraction of λ coming from σ-neutral is (16 +- 5)%. The single- and double V 0 production was used to determine the associated s anti-s production rate and single s-quark production rate. 13 refs., 7 figs., 3 tabs
Wang, Xuefeng; Andrews, Lester; Gagliardi, Laura
2008-02-28
Laser-ablated Th atoms react with molecular hydrogen to give thorium hydrides and their dihydrogen complexes during condensation in excess neon and hydrogen for characterization by matrix infrared spectroscopy. The ThH2, ThH4, and ThH4(H2)x (x = 1-4) product molecules have been identified through isotopic substitution (HD, D2) and comparison to frequencies calculated by density functional theory and the coupled-cluster, singles, doubles (CCSD) method and those observed previously in solid argon. Theoretical calculations show that the Th-H bond in ThH4 is the most polarized of group 4 and uranium metal tetrahydrides, and as a result, a strong attractive "dihydrogen" interaction was found between the oppositely charged hydride and H2 ligands ThH4(H2)x. This bridge-bonded dihydrogen complex structure is different from that recently computed for tungsten and uranium hydride super dihydrogen complexes but is similar to that recently called the "dihydrogen bond" (Crabtree, R. H. Science 1998, 282, 2000). Natural electron configurations show small charge flow from the Th center to the dihydrogen ligands.
Toroidally symmetric/asymmetric effect on the divertor flux due to neon/nitrogen seeding in LHD
Directory of Open Access Journals (Sweden)
H. Tanaka
2017-08-01
Full Text Available Toroidal distributions of divertor particle flux during neon (Ne and nitrogen (N2 seeded discharges were investigated in the Large Helical Device (LHD. By using 14 toroidally distributed divertor probe arrays, which were positioned at radially inner side where the divertor flux concentrates in the inward-shifted magnetic axis configuration, it is found that Ne puffing leads to toroidally quasi-uniform reduction of divertor particle fluxes; whereas toroidally localized reductions were observed with N2 puffing. The toroidally asymmetric reduction pattern with N2 puffing is strongly related to the magnetic field structure around the N2 puffing port. Assuming that nitrogen particles do not recycle, EMC3-EIRENE simulation shows similar reduction pattern with the experiment around the N2 puffing port.
Gd-123 bulk field pole magnets cooled with condensed neon for axial-gap type synchronous motor
International Nuclear Information System (INIS)
Sano, T.; Kimura, Y.; Sugyo, D.; Yamaguchi, K.; Izumi, M.; Ida, T.; Sugimoto, H.; Miki, M.
2008-01-01
We have conducted to develop an axial-gap type synchronous propulsion motor with Gd-bulk HTS field pole magnets. It has been established on the fundamental technology upon the liquid nitrogen cooling. In the present study, we aimed an output improvement of the motor by the magnetic flux density enhancement of the bulk HTS, in a word, the trapped magnetic flux density on the HTS bulk. The output of the motor depends on the physics of the motor, the magnetic flux density, and the electric current density flowing through the armature. We have employed a condensed neon with a helium GM refrigerator. The bulk HTS placed on the rotor disk inside the motor frame was successfully cooled down with circulating condensed neon. The temperature at the bulk HTS surface reached 38 K. Upon magnetization, we developed controlled magnetic field density distribution coil (CMDC) composed of a couple of pulsed copper armature coil. In the magnetization procedure, with decreasing magnetization temperature, minute by minute, after Sander and Kamijyo that the step cooling magnetization method was used. In addition, the CMDC coil has enabled to control the applied flux distribution. Three parameters as the temperature, the applied magnetic field, and the effective applied flux density distribution were changed within eight times pulsed magnetizations in total. Up to 4th pulsed magnetization, we kept (1st step) high temperature, and subsequent pulsed magnetizations were done at low temperature. As a result, the highest maximum trapped magnetic flux density was reached 1.31 T, about 2.5 times compared to the value obtained upon cooling with liquid nitrogen. Consequently, the output of the motor has been enhanced to 25 kW from 10 kW taken in the previous operation
National Ecological Observatory Network's (NEON) future role in US carbon cycling and budgets
Loescher, H. W.
2015-12-01
The US National Ecological Observatory Network (NEON) is a National Science Foundation investment designed to observe the impacts of large-scale environment changes on the nation's ecosystems for 30 years with rigorous consistency. NEON does this through the construction (and operations) of new physical infrastructure and data infrastructure distributed across the North American Continent. This includes 47 terrestrial and 32 aquatic sites. Key to its design is its ability to provide ecosystem-scale carbon measurements of carbon stores, fluxes, processes—and the means to scale them from the local-to regional scales via remote sensed aircraft. NEON design NEON will be collecting these carbon data as a facility and providing openly providing them. NEON will not preform any high-level synthesis, rather the carbon data is an open resource for research, private and public communities, alike. Overall, these data are also harmonized with other international carbon-based infrastructures to facilitate cross-continental understanding and global carbon syntheses. Products, engagement and harmonization of data to facilitate syntheses will be discussed.
Study of reverse Brayton cryocooler with Helium-Neon mixture for HTS cable
Dhillon, A. K.; Ghosh, P.
2017-12-01
As observed in the earlier studies, helium is more efficient than neon as a refrigerant in a reverse Brayton cryocooler (RBC) from the thermodynamic point of view. However, the lower molecular weight of helium leads to higher refrigerant inventory as compared to neon. Thus, helium is suitable to realize the high thermodynamic efficiency of RBC whereas neon is appropriate for the compactness of the RBC. A binary mixture of helium and neon can be used to achieve high thermodynamic efficiency in the compact reverse Brayton cycle (RBC) based cryocooler. In this paper, an attempt has been made to analyze the thermodynamic performance of the RBC with a binary mixture of helium and neon as the working fluid to provide 1 kW cooling load for high temperature superconductor (HTS) power cables working with a temperature range of 50 K to 70 K. The basic RBC is simulated using Aspen HYSYS V8.6®, a commercial process simulator. Sizing of each component based on the optimized process parameters for each refrigerant is performed based on a computer code developed using Engineering Equation Solver (EES-V9.1). The recommendation is provided for the optimum mixture composition of the refrigerant based on the trade-off factors like thermodynamic efficiency such as the exergy efficiency and equipment considerations. The outcome of this study may be useful for recommending a suitable refrigerant for the RBC operating at a temperature level of 50 K to 70 K.
Helium and neon diffusion in pure hematite (α-Fe2O3) crystal lattice
Balout, Hilal; Roques, Jérôme; Gautheron, Cécile; Tassan-Got, Laurent
2016-04-01
Hematite (α-Fe2O3) has the corundum-type structure and is relatively present on Earth and Mars surface associated to ore mineral precipitation or as a weathering phase. He and Ne retention in such mineral has been intensively investigated experimentally because of the potential use of (U-Th-Sm)/(He-Ne) chronometer and thermochronometer. Therefore, the He/Ne diffusion in hematite crystal is an important issue for the interpretation of (U-Th)/(He-Ne) thermochronometric ages. For this purpose an accurate investigation of helium and neon diffusion in hematite crystal lattice has been achieved by computational multi-scale approach. Different insertion sites and diffusion pathways are first characterized where the spin polarized density functional theory (sp-DFT) approach coupled to the nudged elastic band (NEB) method is used to determine the migration energies between the insertion sites. Then, a statistical method, based on transition state theory (TST), is used to compute the jump probability between sites. The previous results are used as input data in a 3D random walk simulation, which permits to determine the effective activation energy and diffusion coefficient. Using the He/Ne diffusion coefficients, the closure temperature Tc has been calculated. For typical grain size of 100 microns, Tc will be of 116° C and 297° C for He and Ne atoms, respectively. These results Show that He and Ne atoms are highly retained in the crystal lattice at surface temperature. The obtained diffusion coefficients confirm that He/Ne retentively power in hematite lattice is very important, allowing a large range of different geological applications such the measurement of hematite crystallization ages on Earth and Mars.
Demonstrating a directional detector based on neon for characterizing high energy neutrons
Hexley, Allie
2016-03-01
MITPC is a gas-based time projection chamber used for detecting fast, MeV-scale neutrons. The standard version of the detector relies on a mixture of 600 torr gas composed of 87.5% helium-4 and 12.5% tetrafluoromethane for precisely measuring the energy and direction of neutron-induced nuclear recoils. I describe studies performed with a prototype detector investigating the use of neon, as a replacement for helium-4, in the gas mixture. My discussion focuses on the advantages of neon as the fast neutron target for high energy neutron events (100 MeV) and a demonstration that the mixture will be effective for this event class. I show that the achievable gain and transverse diffusion of drifting electrons in the neon mixture are acceptable and that the detector uptime lost due to voltage breakdowns in the amplification plane is negligible, compared to 20% with the helium-4 mixture.
Thomas U. Kampe; Brian R. Johnson; Michele Kuester; Michael. Keller
2010-01-01
The National Ecological Observatory Network (NEON) is an ecological observation platform for discovering, understanding and forecasting the impacts of climate change, land use change, and invasive species on continental-scale ecology. NEON will operate for 30 years and gather long-term data on ecological response changes and on feedbacks with the geosphere, hydrosphere...
Ionization of neon by intermediate energy carbon ions
International Nuclear Information System (INIS)
McLawhorn, S.L.; Toburen, L.H.; Shinpaugh, J.L.; Justiniano, E.L.B.; Dingfelder, M.; Toekesi, K.; Sulik, B.; Sigmund, P.; Schinner, A.; Reinhold, C.; Schultz, D.
2007-01-01
Complete text of publication follows. During the past few years there has been increasing interest in ionization of atomic and molecular targets by intermediate-energy dressed and partially dressed ions. These systems are particularly challenging to describe theoretically owing to screening of the projectile nuclear charge by bound electrons, interactions of projectile electrons with target electrons, and the large number of possible exit channels. At ECU we have initiated measurements of the doubly-differential ionization cross sections, differential in ejected electron energy and emission energy, for carbon ions of different initial charge states with atomic and molecular targets. In this presentation we compare those results with calculations being conducted at several institutions. For this presentation we will focus on electron emission from neon following interactions with carbon ions with energies from 0.067 MeV/u to 0.35 MeV/u and incident charge states from C + to C 3+ . Electron energies from 10 to 1500 eV are observed at emission angles from 20 to 120 degrees. The calculations separate the process into ionization of the target by the screened incident nucleus and the ionization of the target by the screened target nucleus. By summing these components in the rest frame of the target we can compare to the measured electron spectra. Figure 1 shows the single differential cross sections for ejection of electrons in C + -Ne collisions. Note the small contribution from ionization of the projectile. As the energy increases the contribution from projectile ionization increases; likewise as the ion energy decreases that contribution decreases. The excellent agreement shown in Figure 1 provides confidence to our use of Bohr theory for this energy range for this target. Doubly-differential cross sections based on the Classical Trajectory Monte Carlo (CTMC) techniques are compared with measurements in Fig. 2 for electron emission at 30 degrees. Again, excellent
Energy Technology Data Exchange (ETDEWEB)
Andreev, V.; Belousov, A.; Fomenko, A.; Gogitidze, N.; Lebedev, A.; Malinovski, E.; Soloviev, Y.; Vazdik, Y. [Lebedev Physical Institute, Moscow (Russian Federation); Baghdasaryan, A.; Zohrabyan, H. [Yerevan Physics Institute, Yerevan (Armenia); Begzsuren, K.; Ravdandorj, T. [Institute of Physics and Technology of the Mongolian Academy of Sciences, Ulaanbaatar (Mongolia); Bertone, V. [Vrije University, Department of Physics and Astronomy, Amsterdam (Netherlands); National Institute for Subatomic Physics (NIKHEF), Amsterdam (Netherlands); Bolz, A.; Britzger, D.; Huber, F.; Sauter, M.; Schoening, A. [Universitaet Heidelberg, Physikalisches Institut, Heidelberg (Germany); Boudry, V.; Specka, A. [LLR, Ecole Polytechnique, CNRS/IN2P3, Palaiseau (France); Brandt, G. [Universitaet Goettingen, II. Physikalisches Institut, Goettingen (Germany); Brisson, V.; Jacquet, M.; Pascaud, C.; Zhang, Z.; Zomer, F. [LAL, Universite Paris-Sud, CNRS/IN2P3, Orsay (France); Buniatyan, A.; Newman, P.R.; Thompson, P.D. [University of Birmingham, School of Physics and Astronomy, Birmingham (United Kingdom); Bylinkin, A. [Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region (Russian Federation); Bystritskaya, L.; Fedotov, A. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Campbell, A.J.; Dodonov, V.; Eckerlin, G.; Elsen, E.; Fleischer, M.; Gayler, J.; Ghazaryan, S.; Haidt, D.; Jung, H.; Katzy, J.; Kleinwort, C.; Kruecker, D.; Krueger, K.; Levonian, S.; Lipka, K.; List, B.; List, J.; Meyer, A.B.; Meyer, J.; Niebuhr, C.; Olsson, J.E.; Pirumov, H.; Pitzl, D.; Placakyte, R.; Schmitt, S.; Sefkow, F.; South, D.; Steder, M.; Wuensch, E.; Zlebcik, R. [DESY, Hamburg (Germany); Cantun Avila, K.B.; Contreras, J.G. [CINVESTAV, Departamento de Fisica Aplicada, Merida, Yucatan (Mexico); Cerny, K.; Salek, D.; Valkarova, A.; Zacek, J. [Charles University, Faculty of Mathematics and Physics, Prague (Czech Republic); Chekelian, V.; Grindhammer, G.; Kiesling, C.; Lobodzinski, B. [Max-Planck-Institut fuer Physik, Munich (Germany); Cvach, J.; Hladky, J.; Reimer, P. [Academy of Sciences of the Czech Republic, Institute of Physics, Prague (Czech Republic); Currie, J. [Durham University, Institute for Particle Physics Phenomenology, Ogden Centre for Fundamental Physics, Durham (United Kingdom); Dainton, J.B.; Gabathuler, E.; Greenshaw, T.; Klein, M.; Kostka, P.; Kretzschmar, J.; Laycock, P.; Maxfield, S.J.; Mehta, A.; Patel, G.D. [University of Liverpool, Department of Physics, Liverpool (United Kingdom); Daum, K.; Meyer, H. [Fachbereich C, Universitaet Wuppertal, Wuppertal (Germany); Diaconu, C.; Hoffmann, D.; Vallee, C. [Aix Marseille Universite, CNRS/IN2P3, CPPM UMR 7346, Marseille (France); Dobre, M.; Rotaru, M. [Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering (IFIN-HH), Bucharest (Romania); Egli, S.; Horisberger, R.; Ozerov, D. [Paul Scherrer Institute, Villigen (Switzerland); Favart, L.; Grebenyuk, A.; Hreus, T.; Janssen, X.; Roosen, R.; Mechelen, P.Van [Brussels and Universiteit Antwerpen, Inter-University Institute for High Energies ULB-VUB, Antwerp (Belgium); Feltesse, J.; Schoeffel, L. [Irfu/SPP, CE Saclay, Gif-sur-Yvette (France); Gehrmann, T.; Mueller, K.; Niehues, J.; Robmann, P.; Straumann, U.; Truoel, P. [Physik-Institut der Universitaet Zuerich, Zurich (Switzerland); Goerlich, L.; Mikocki, S.; Nowak, G.; Sopicki, P. [Polish Academy of Sciences, Institute of Nuclear Physics, Krakow (Poland); Gouzevitch, M.; Petrukhin, A. [IPNL, Universite Claude Bernard Lyon 1, CNRS/IN2P3, Villeurbanne (France); Grab, C.; Huss, A. [ETH Zuerich, Institut fuer Teilchenphysik, Zurich (Switzerland); Gwenlan, C.; Radescu, V. [Oxford University, Department of Physics, Oxford (United Kingdom); Henderson, R.C.W. [University of Lancaster, Department of Physics, Lancaster (United Kingdom); Jung, A.W. [Purdue University, Department of Physics and Astronomy, West Lafayette, IN (United States); Kapichine, M.; Morozov, A.; Spaskov, V. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Kogler, R. [Universitaet Hamburg, Institut fuer Experimentalphysik, Hamburg (Germany); Landon, M.P.J.; Rizvi, E.; Traynor, D. [Queen Mary University of London, School of Physics and Astronomy, London (United Kingdom); Lange, W.; Naumann, T. [DESY, Zeuthen (Germany); Martyn, H.U. [I. Physikalisches Institut der RWTH, Aachen (Germany); Perez, E. [CERN, Geneva (Switzerland); Picuric, I.; Raicevic, N. [University of Montenegro, Faculty of Science, Podgorica (Montenegro); Polifka, R. [Charles University, Faculty of Mathematics and Physics, Prague (Czech Republic); University of Toronto, Department of Physics, Toronto, ON (Canada); Rabbertz, K. [Karlsruher Institut fuer Technologie (KIT), Institut fuer Experimentelle Teilchenphysik (ETP), Karlsruhe (Germany); Rostovtsev, A. [Institute for Information Transmission Problems RAS, Moscow (Russian Federation); Sankey, D.P.C. [STFC, Rutherford Appleton Laboratory, Didcot, Oxfordshire (United Kingdom); Sauvan, E. [Aix Marseille Universite, CNRS/IN2P3, CPPM UMR 7346, Marseille (France); Universite de Savoie, CNRS/IN2P3, LAPP, Annecy-le-Vieux (France); Shushkevich, S. [Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); Stella, B. [Universita di Roma Tre, Dipartimento di Fisica, Rome (Italy); INFN Roma 3 (Italy); Sutton, M.R. [University of Sussex, Department of Physics and Astronomy, Brighton (United Kingdom); Sykora, T. [Brussels and Universiteit Antwerpen, Inter-University Institute for High Energies ULB-VUB, Antwerp (Belgium); Charles University, Faculty of Mathematics and Physics, Prague (Czech Republic); Tsakov, I. [Institute for Nuclear Research and Nuclear Energy, Sofia (Bulgaria); Tseepeldorj, B. [Institute of Physics and Technology of the Mongolian Academy of Sciences, Ulaanbaatar (MN); Ulaanbaatar University, Ulaanbaatar (MN); Wegener, D. [TU Dortmund, Institut fuer Physik, Dortmund (DE); Collaboration: H1 Collaboration
2017-11-15
The strong coupling constant α{sub s} is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 collaboration using next-to-next-to-leading order (NNLO) QCD predictions. The dependence of the NNLO predictions and of the resulting value of α{sub s}(m{sub Z}) at the Z-boson mass m{sub Z} are studied as a function of the choice of the renormalisation and factorisation scales. Using inclusive jet and dijet data together, the strong coupling constant is determined to be α{sub s}(m{sub Z}) = 0.1157(20){sub exp}(29){sub th}. Complementary, α{sub s}(m{sub Z}) is determined together with parton distribution functions of the proton (PDFs) from jet and inclusive DIS data measured by the H1 experiment. The value α{sub s}(m{sub Z}) = 0.1142(28){sub tot} obtained is consistent with the determination from jet data alone. The impact of the jet data on the PDFs is studied. The running of the strong coupling is tested at different values of the renormalisation scale and the results are found to be in agreement with expectations. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Wu, Yaoting; Li, Siming; Gogotsi, Natalie; Zhao, Tianshuo; Fleury, Blaise; Kagan, Cherie R.; Murray, Christopher B.; Baxter, Jason B.
2017-02-16
Two species of monodisperse nanocrystals (NCs) can self-assemble into a variety of complex 2D and 3D periodic structures, or binary NC superlattice (BNSL) films, based on the relative number and size of the NCs. BNSL films offer great promise for both fundamental scientific studies and optoelectronic applications; however, the utility of as-assembled structures has been limited by the insulating ligands that originate from the synthesis of NCs. Here we report the application of an in situ ligand exchange strategy at a liquid–air interface to replace the long synthesis ligands with short ligands while preserving the long-range order of BNSL films. This approach is demonstrated for BNSL structures consisting of PbSe NCs of different size combinations and ligands of interest for photovoltaic devices, infrared detectors, and light-emitting diodes. To confirm enhanced coupling introduced by ligand exchange, we show ultrafast (~1 ps) directional carrier transfer across the type-I heterojunction formed by NCs of different sizes within ligand-exchanged BNSL films. In conclusion, this approach shows the potential promise of functional BNSL films, where the local and long-range energy landscape and electronic coupling can be adjusted by tuning NC composition, size, and interparticle spacing.
Fainstein, A; Lanzillotti-Kimura, N D; Jusserand, B; Perrin, B
2013-01-18
We show that distributed Bragg reflector GaAs/AlAs vertical cavities designed to confine photons are automatically optimal to confine phonons of the same wavelength, strongly enhancing their interaction. We study the impulsive generation of intense coherent and monochromatic acoustic phonons by following the time evolution of the elastic strain in picosecond-laser experiments. Efficient optical detection is assured by the strong phonon backaction on the high-Q optical cavity mode. Large optomechanical factors are reported (~THz/nm range). Pillar cavities based in these structures are predicted to display picogram effective masses, almost perfect sound extraction, and threshold powers for the stimulated emission of phonons in the range μW-mW, opening the way for the demonstration of phonon "lasing" by parametric instability in these devices.
Comparison of boron and neon damage effects in boron ion-implanted resistors
International Nuclear Information System (INIS)
MacIver, B.A.
1975-01-01
Boron and neon damage implants were used in fabricating integrated-circuit resistors in silicon. Resistor properties were studied as functions of damaging ion species and dose. Sheet resistances in the 10 000 Ω/square range were obtained with low temperature and voltage sensitivities and d.c. isolation. (author)
Improved discovery of NEON data and samples though vocabularies, workflows, and web tools
Laney, C. M.; Elmendorf, S.; Flagg, C.; Harris, T.; Lunch, C. K.; Gulbransen, T.
2017-12-01
The National Ecological Observatory Network (NEON) is a continental-scale ecological observation facility sponsored by the National Science Foundation and operated by Battelle. NEON supports research on the impacts of invasive species, land use change, and environmental change on natural resources and ecosystems by gathering and disseminating a full suite of observational, instrumented, and airborne datasets from field sites across the U.S. NEON also collects thousands of samples from soil, water, and organisms every year, and partners with numerous institutions to analyze and archive samples. We have developed numerous new technologies to support processing and discovery of this highly diverse collection of data. These technologies include applications for data collection and sample management, processing pipelines specific to each collection system (field observations, installed sensors, and airborne instruments), and publication pipelines. NEON data and metadata are discoverable and downloadable via both a public API and data portal. We solicit continued engagement and advice from the informatics and environmental research communities, particularly in the areas of data versioning, usability, and visualization.
International Nuclear Information System (INIS)
Suzuki, Masao; Tsuruoka, Chizuru; Kanai, Tatsuaki; Kato, Takeshi; Yatagai, Fumio; Watanabe, Masami
2006-01-01
We investigated the linear energy transfer (LET) dependence of mutation induction on the hypoxanthine-guanine phosphoribosyl transferase (HPRT) locus in normal human fibroblast-like cells irradiated with accelerated neon-ion beams. The cells were irradiated with neon-ion beams at various LETs ranging from 63 to 335 keV/μm. Neon-ion beams were accelerated by the Riken Ring Cyclotron at the Institute of Physical and Chemical Research in Japan. Mutation induction at the HPRT locus was detected to measure 6-thioguanine-resistant clones. The mutation spectrum of the deletion pattern of exons of mutants was analyzed using the multiplex polymerase chain reaction (PCR). The dose-response curves increased steeply up to 0.5 Gy and leveled off or decreased between 0.5 and 1.0 Gy, compared to the response to 137 Cs γ-rays. The mutation frequency increased up to 105 keV/μm and then there was a downward trend with increasing LET values. The deletion pattern of exons was non-specific. About 75-100% of the mutants produced using LETs ranging from 63 to 335 keV/μm showed all or partial deletions of exons, while among γ-ray-induced mutants 30% showed no deletions, 30% partial deletions and 40% complete deletions. These results suggested that the dose-response curves of neon-ion-induced mutations were dependent upon LET values, but the deletion pattern of DNA was not
International Nuclear Information System (INIS)
Li Guangzuo
1989-01-01
Using a simplified method, the concentrations of 85 Kr leaking into the air of a workshop and its surroundings, where a neon lamp production line was to be installed, were calculated. The doses to the workers and inhabitants nearby were also estimated. Thus, the evaluation of 85 Kr enviromental contamination caused by imported equipments was made feasible
Smith, D.; Metzger, S.; Taylor, J. R.
2013-12-01
A fundamental role of the National Ecological Observatory Network (NEON) is to offer high quality and transparent data to the community. Yet, data is seemingly useless without the ability to assess its validity. Therefore, it is essential for NEON to implement a method that allows users to assess the quality of its data. Since tower-based sensors represent a large portion of NEON's automated measurements, it is critical that any ambiguity in sensor measurements are captured and quantified. Initial data quality of tower sensor measurements will be based on a suite of quality assurance and quality control (QA/QC) analyses as well as sensor flags. This will result in 'data products' (data produced by NEON) being accompanied with a set of 'quality flags' (QA/QC and sensor flags). However, the magnitude of data that will be generated by NEON requires developing a framework for summarizing data quality information. In order to accommodate varying use cases and levels of expertise, such a framework should provide several levels of detail. NEON is not alone in this challenge, as there is a continued need for large data sets to answer the research questions of tomorrow. Thus, a framework was created with the intention of meeting the needs of NEON, while maintaining interoperability across disciplines. The framework consists of presenting quality information for each data product through two separate schemes; a quality report and a quality summary. The quality report presents the results of specific quality flags as they relate to individual observations. For example, the quality report for a thirty-minute temperature average, sampled at a rate of 1 Hz, allows the user to differentiate the 1800 outcomes for the QA/QC analyses and sensor flags. The quality summary instead provides a 'quality metric' for each quality flag. A quality metric summarizes, as a percentage, the results of the QA/QC analyses and sensor flags for the observations that were used to calculate a data
NEON Collaborative Data Collection Campaign at Pacific South West Site in California
Kampe, T. U.; Leisso, N.; Krause, K.; Musinsky, J.; Petroy, S. B.; Wasser, L. A.; Cawse-Nicholson, K.; van Aardt, J. A.; Schaaf, C.; Strahler, A. H.; Serbin, S. P.
2013-12-01
The National Ecological Observatory Network (NEON) is a continental-scale observatory that will collect biological, chemical and geophysical data over the continental United States in order to study biodiversity, landcover change, climate change and invasive species. In June 2013, a large-scale data collection took place over NEON's Pacific South West (PSW) site 17 in CA, USA. Data were collected in the San Joaquin Experimental Range and the Sierra National Forest. NEON's AOP (Airborne Observation Platform) acquired high spatial resolution hyperspectral data (~1m pixels), waveform lidar, discrete lidar, and RGB imagery over all three sites. A field team simultaneously collected atmospheric and vegetation inventory data, including tree locations, height, diameter-at-breast-height (DBH), species, and spectral data. The NEON collect was centered within a collaboration of multiple research entities, including NASA, Rochester Institute of Technology (RIT), University of Massachusetts (Boston; UMB, and Lowell; UML), Boston University (BU), and the University of Wisconsin, Madison (UWM). NASA's AVIRIS and MASTER sensors were flown over a wider area encompassing the NEON sites, with AVIRIS acquiring hyperspectral data (224 bands) at approximately 30m spatial resolution, and MASTER acquiring multispectral thermal data (50 bands) at approximately 50m spatial resolution. These data will be downscaled to approximate theoretical HyspIRI data (60m spatial resolution) as part of a large collection of preparatory research. Concurrently, a variety of university teams were active in the field: RIT collected ground-based lidar, leaf area index (LAI), herbaceous biomass measurements, wide-angle photographs, and spectral measurements. Data were collected over 20 80x80m sites, centered on existing 20x20m NEON sites. This data set will be used to inform synthetic scene design and to study the impact of sub-pixel structural variation on pixel-level spectral response; The BU, UMB, and UML
Ip, Brenda C K; Shenderovich, Ilya G; Tolstoy, Peter M; Frydel, Jaroslaw; Denisov, Gleb S; Buntkowsky, Gerd; Limbach, Hans-Heinrich
2012-11-26
We have studied the hydrogen bond interactions of (15)N labeled 4-methylpyridine (4-MP) with pentachlorophenol (PCP) in the solid state and in polar solution using various NMR techniques. Previous spectroscopic, X-ray, and neutron crystallographic studies showed that the triclinic 1:1 complex (4-MPPCP) exhibits the strongest known intermolecular OHN hydrogen bond in the solid state. By contrast, deuteration of the hydrogen bond gives rise to the formation of a monoclinic structure exhibiting a weaker hydrogen bond. By performing NMR experiments at different deuterium fractions and taking advantage of dipolar (1)H-(15)N recoupling under combined fast MAS and (1)H decoupling, we provide an explanation of the origin of the isotopic polymorphism of 4-MPPCP and improve previous chemical shift correlations for OHN hydrogen bonds. Because of anharmonic ground state vibrations, an ODN hydrogen bond in the triclinic form exhibits a shorter oxygen-hydron and a longer oxygen-nitrogen distance as compared to surrounding OHN hydrogen bonds, which also implies a reduction of the local dipole moment. The dipole-dipole interaction between adjacent coupled OHN hydrogen bonds which determines the structure of triclinic 4-MPPCP is then reduced by deuteration, and other interactions become dominant, leading to the monoclinic form. Finally, the observation of stronger OHN hydrogen bonds by (1)H NMR in polar solution as compared to the solid state is discussed.
Directory of Open Access Journals (Sweden)
Finkelstein Alexei V
2007-07-01
Full Text Available Abstract Background The prediction of ligand binding or protein structure requires very accurate force field potentials – even small errors in force field potentials can make a 'wrong' structure (from the billions possible more stable than the single, 'correct' one. However, despite huge efforts to optimize them, currently-used all-atom force fields are still not able, in a vast majority of cases, even to keep a protein molecule in its native conformation in the course of molecular dynamics simulations or to bring an approximate, homology-based model of protein structure closer to its native conformation. Results A strict analysis shows that a specific coupling of multi-atom Van der Waals interactions with covalent bonding can, in extreme cases, increase (or decrease the interaction energy by about 20–40% at certain angles between the direction of interaction and the covalent bond. It is also shown that on average multi-body effects decrease the total Van der Waals energy in proportion to the square root of the electronic component of dielectric permittivity corresponding to dipole-dipole interactions at small distances, where Van der Waals interactions take place. Conclusion The study shows that currently-ignored multi-atom Van der Waals interactions can, in certain instances, lead to significant energy effects, comparable to those caused by the replacement of atoms (for instance, C by N in conventional pairwise Van der Waals interactions.
NEON's eddy-covariance: interoperable flux data products, software and services for you, now
Metzger, S.; Desai, A. R.; Durden, D.; Hartmann, J.; Li, J.; Luo, H.; Durden, N. P.; Sachs, T.; Serafimovich, A.; Sturtevant, C.; Xu, K.
2017-12-01
Networks of eddy-covariance (EC) towers such as AmeriFlux, ICOS and NEON are vital for providing the necessary distributed observations to address interactions at the soil-vegetation-atmosphere interface. NEON, close to full operation with 47 tower sites, will represent the largest single-provider EC network globally. Its standardized observation and data processing suite is designed specifically for inter-site comparability and analysis of feedbacks across multiple spatial and temporal scales. Furthermore, NEON coordinates EC with rich contextual observations such as airborne remote sensing and in-situ sampling bouts. In January 2018 NEON enters its operational phase, and EC data products, software and services become fully available to the science community at large. These resources strive to incorporate lessons-learned through collaborations with AmeriFlux, ICOS, LTER and others, to suggest novel systemic solutions, and to synergize ongoing research efforts across science communities. Here, we present an overview of the ongoing product release, alongside efforts to integrate and collaborate with existing infrastructures, networks and communities. Near-real-time heat, water and carbon cycle observations in "basic" and "expanded", self-describing HDF5 formats become accessible from the NEON Data Portal, including an Application Program Interface. Subsequently, they are ingested into the AmeriFlux processing pipeline, together with inclusion in FLUXNET globally harmonized data releases. Software for reproducible, extensible and portable data analysis and science operations management also becomes available. This includes the eddy4R family of R-packages underlying the data product generation, together with the ability to directly participate in open development via GitHub version control and DockerHub image hosting. In addition, templates for science operations management include a web-based field maintenance application and a graphical user interface to simplify
Positron annihilation in low-temperature rare gases. II. Argon and neon
International Nuclear Information System (INIS)
Canter, K.F.; Roellig, L.O.
1975-01-01
Lifetime measurements of slow-positron and ortho-positronium (o-Ps) annihilation were made in argon and neon gases at room temperature and below. The argon experiments cover the temperature range 115 to 300 0 K and the density range 0.0356 to 0.0726 g/cm 3 (approximately equal to 20 to 40 amagat). The slow-positron spectra in argon exhibit a departure from free-positron annihilation below 200 0 K. The departure becomes more marked as the temperature is lowered. No deviation from free o-Ps pickoff annihilation is observed in argon at low temperatures. The neon measurements cover the temperature range 30 to 300 0 K and the density range 0.032 to 0.89 g/cm 3 (approximately equal to 35 to 980 amagat). No effect of temperature on the slow-positron spectra throughout the temperature and density ranges investigated in neon is observed. The spectra are very exponential with a corresponding decay rate which is temperature as well as time independent and is directly proportional to density over the ranges investigated. The o-Ps data are more eventful in that the o-Ps lifetime at near-liquid densities is approximately 20 nsec, a factor of nearly 4 greater than the value obtained using the pickoff-annihilation coefficient obtained at lower densities. This is evidence for positronium-induced cavities in low-temperature neon. A brief discussion of the argon and neon results is given in the context of the explanations offered for the low-temperature effects observed in helium gas
NEON: High Frequency Monitoring Network for Watershed-Scale Processes and Aquatic Ecology
Vance, J. M.; Fitzgerald, M.; Parker, S. M.; Roehm, C. L.; Goodman, K. J.; Bohall, C.; Utz, R.
2014-12-01
Networked high frequency hydrologic and water quality measurements needed to investigate physical and biogeochemical processes at the watershed scale and create robust models are limited and lacking standardization. Determining the drivers and mechanisms of ecological changes in aquatic systems in response to natural and anthropogenic pressures is challenging due to the large amounts of terrestrial, aquatic, atmospheric, biological, chemical, and physical data it requires at varied spatiotemporal scales. The National Ecological Observatory Network (NEON) is a continental-scale infrastructure project designed to provide data to address the impacts of climate change, land-use, and invasive species on ecosystem structure and function. Using a combination of standardized continuous in situ measurements and observational sampling, the NEON Aquatic array will produce over 200 data products across its spatially-distributed field sites for 30 years to facilitate spatiotemporal analysis of the drivers of ecosystem change. Three NEON sites in Alabama were chosen to address linkages between watershed-scale processes and ecosystem changes along an eco-hydrological gradient within the Tombigbee River Basin. The NEON Aquatic design, once deployed, will include continuous measurements of surface water physical, chemical, and biological parameters, groundwater level, temperature and conductivity and local meteorology. Observational sampling will include bathymetry, water chemistry and isotopes, and a suite of organismal sampling from microbes to macroinvertebrates to vertebrates. NEON deployed a buoy to measure the temperature profile of the Black Warrior River from July - November, 2013 to determine the spatiotemporal variability across the water column from a daily to seasonal scale. In July 2014 a series of water quality profiles were performed to assess the contribution of physical and biogeochemical drivers over a diurnal cycle. Additional river transects were performed
Strong Interactive Massive Particles from a Strong Coupled Theory
DEFF Research Database (Denmark)
Yu. Khlopov, Maxim; Kouvaris, Christoforos
2008-01-01
(-2). These excessive techniparticles are all captured by $^4He$, creating \\emph{techni-O-helium} $tOHe$ ``atoms'', as soon as $^4He$ is formed in Big Bang Nucleosynthesis. The interaction of techni-O-helium with nuclei opens new paths to the creation of heavy nuclei in Big Bang Nucleosynthesis. Due...
Yun, Hyeong Jin; Paik, Taejong; Diroll, Benjamin; Edley, Michael E; Baxter, Jason B; Murray, Christopher B
2016-06-15
Light absorption and electron injection are important criteria determining solar energy conversion efficiency. In this research, monodisperse CdSe quantum dots (QDs) are synthesized with five different diameters, and the size-dependent solar energy conversion efficiency of CdSe quantum dot sensitized solar cell (QDSSCs) is investigated by employing the atomic inorganic ligand, S(2-). Absorbance measurements and transmission electron microscopy show that the diameters of the uniform CdSe QDs are 2.5, 3.2, 4.2, 6.4, and 7.8 nm. Larger CdSe QDs generate a larger amount of charge under the irradiation of long wavelength photons, as verified by the absorbance results and the measurements of the external quantum efficiencies. However, the smaller QDs exhibit faster electron injection kinetics from CdSe QDs to TiO2 because of the high energy level of CBCdSe, as verified by time-resolved photoluminescence and internal quantum efficiency results. Importantly, the S(2-) ligand significantly enhances the electronic coupling between the CdSe QDs and TiO2, yielding an enhancement of the charge transfer rate at the interfacial region. As a result, the S(2-) ligand helps improve the new size-dependent solar energy conversion efficiency, showing best performance with 4.2-nm CdSe QDs, whereas conventional ligand, mercaptopropionic acid, does not show any differences in efficiency according to the size of the CdSe QDs. The findings reported herein suggest that the atomic inorganic ligand reinforces the influence of quantum confinement on the solar energy conversion efficiency of QDSSCs.
Energy Technology Data Exchange (ETDEWEB)
Bouis, F
1999-10-14
Two strongly correlated electron systems are considered in this work, Kondo insulators and high Tc cuprates. Experiments and theory suggest on one hand that the Kondo screening occurs on a rather short length scale and on the other hand that the Kondo coupling is renormalized to infinity in the low energy limit. The strong coupling limit is then the logical approach although the real coupling is moderate. A systematic development is performed around this limit in the first part. The band structure of these materials is reproduced within this scheme. Magnetic fluctuations are also studied. The antiferromagnetic transition is examined in the case where fermionic excitations are shifted to high energy. In the second part, the Popov and Fedotov representation of spins is used to formulate the Kondo and the antiferromagnetic Heisenberg model in terms of a non-polynomial action of boson fields. In the third part the properties of high Tc cuprates are explained by a change of topology of the Fermi surface. This phenomenon would happen near the point of optimal doping and zero temperature. It results in the appearance of a density wave phase in the under-doped regime. The possibility that this phase has a non-conventional symmetry is considered. The phase diagram that described the interaction and coexistence of density wave and superconductivity is established in the mean-field approximation. The similarities with the experimental observations are numerous in particular those concerning the pseudo-gap and the behavior of the resistivity near optimal doping. (author)
Last, T.; van Adrichem, P.; de Winter, L.; Hsu, S.; Finders, J.; Wittebrood, F.; van de Kerkhof, M.
2017-03-01
We report a study into intensity-driven mask 3D effects for N7 dark field two-bars in EUVL. For these features, traditional pupil optimization "rules" are advising to center a symmetric leaf shape illumination at the pupil plane location σY = (-0.64, 0.64). Experimentally determined critical dimension Bossungs for this exposure condition however yield an extreme best focus separation due to an additional Bossung tilt appearing at defocus values beyond 20 nm for the bottom trench. The Bossung tilts are caused by a strong coupling between the primary image of the two-bar and its first local pitch-induced self-image. The coupling to the self-image can be suppressed and, hence, the overlapping process window can be enhanced by the application of asymmetric sources, or by using standard dipole 90Y or leaf shape illuminations in combination with optimally placed sub-resolution assist features.
Zhao, Yun; Law, Henry C H; Zhang, Zaijun; Lam, Herman C; Quan, Quan; Li, Guohui; Chu, Ivan K
2015-10-09
In this study we developed a fully automated three-dimensional (3D) liquid chromatography methodology-comprising hydrophilic interaction separation as the first dimension, strong cation exchange fractionation as the second dimension, and low-pH reversed-phase (RP) separation as the third dimension-in conjunction downstream with additional complementary porous graphitic carbon separation, to capture non-retained hydrophilic analytes, for both shotgun proteomics and N-glycomics analyses. The performance of the 3D system alone was benchmarked through the analysis of the total lysate of Saccharomyces cerevisiae, leading to improved hydrophilic peptide coverage, from which we identified 19% and 24% more proteins and peptides, respectively, relative to those identified from a two-dimensional hydrophilic interaction liquid chromatography and low-pH RP chromatography (HILIC-RP) system over the same mass spectrometric acquisition time; consequently, the 3D platform also provided enhanced proteome and protein coverage. When we applied the integrated technology to analyses of the total lysate of primary cerebellar granule neurons, we characterized a total of 2201 proteins and 16,937 unique peptides for this primary cell line, providing one of its most comprehensive datasets. Our new integrated technology also exhibited excellent performance in the first N-glycomics analysis of cynomolgus monkey plasma; we successfully identified 122 proposed N-glycans and 135 N-glycosylation sites from 122 N-glycoproteins, and confirmed the presence of 38 N-glycolylneuraminic acid-containing N-glycans, a rare occurrence in human plasma, through tandem mass spectrometry for the first time. Copyright © 2015 Elsevier B.V. All rights reserved.
Williams, C. D.; Mukhopadhyay, S.
2017-12-01
The origin and acquisition of volatiles within planetary interiors remains a significant challenge in planet formation models. Two common hypotheses are [1] incorporation of nebular volatiles with later addition of chondritic materials or [2] the accretion of solar wind irradiated materials1. Here we use the neon isotopic composition of plume-influenced mid-ocean ridge basalts (MORBs) from the south Atlantic, along with ratios of primordial argon to neon (36Ar/22Ne), to distinguish between these two potential sources of volatiles. Maximum measured 20Ne/22Ne ratios of 12.99 ± 0.03 are significantly higher than the MORB source ratio2 of 12.49 ± 0.04. Mixing between the plume source and the MORB source indicate a lower mantle source region characterized by a 20Ne/22Ne ratio of 13.32 ± 0.17, indistinguishable from an estimate of 13.36 ± 0.09 for nebular gas3. Conversely, the MORB source 20Ne/22Ne and 36Ar/22Ne ratios trend towards chondritic materials. These results support a scenario in which at least two sources, nebular gas and later addition of chondritic materials, contributed volatiles to the mantle during Earth's accretion. Acquisition of nebular volatiles places strong constraints on planet formation models including accretion timescales and the H2 budget of the early Earth. The nebular volatiles are likely sequestered in the large low shear-wave velocity provinces (LLSVPs) at the bottom of the mantle as primordial helium isotopic compositions associated with high 20Ne/22Ne ratio samples display a strong correlation with LLSVPs when deflection of plume conduits is considered. Consequently, LLSVPs are chemically distinct reservoirs sitting atop the core-mantle boundary and contain material with a memory of the nebular disk. 1Moreira, M. 2013. Geochemical Perspectives 2, 229-403. 2Holland, G. & Ballentine, C. J. 2006. Nature 441, 186-191. 3Heber, V. S. et al., 2012. The Astrophysical Journal 759, 121.
Photoionization of excited states of neon-like Mg III
Indian Academy of Sciences (India)
Abstract. The close coupling R-matrix method is used to calculate cross-sections for photoioniza- tion of Mg III from its first three excited states. Configuration interaction wave functions are used to represent two target states of Mg III retained in the R-matrix expansion. The positions and effective quantum numbers for the ...