Theoretical study of the low-lying bound states of O2
Partridge, Harry; Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.
1991-01-01
It is demonstrated that a complete-active-space self-consistent-field (CASSCF) (2p)/MRCI + Q (multireference configuration interaction with a Davidson correction) description in a (13s8p6d 4f2g)/((5s4p3d 2f1g) atomic natural orbits (ANO) basis set supplemented with diffuse functions provides a quantitative description of the six lowest states of O2. The calculated potentials are within 0.05 eV (1.2 kilocal/mol) of accurate experimental results. The importance of substantially expanding the primitive basis set has been investigated, and it is demonstrated that such expansions yield insignificant improvement in the spectroscopic constants. Potential energy curves have also been reported for the weakly bound states of O2. The 5Pi(g) state is estimated to have a D(e) of 0.16 +/- 0.03 eV. The upper bound of D(e) is found to be sufficiently large that the importance of this state as a precursor for the formation of O2 (b 1Sigma(t)(+)) and O(1S) should be reconsidered.
Energy of the low-lying bound S-states of exotic two-muon three-body systems
Khan, Md Abdul
2014-01-01
Energies of the low-lying bound S-states (L=0) of exotic three-body systems, consisting a nuclear core of charge +Ze (Z being atomic number of the core) and two negatively charged valence muons, have been calculated by hyperspherical harmonics expansion method (HHEM). The three-body Schr\\H{o}dinger equation is solved assuming purely Coulomb interaction among the binary pairs of the three-body systems X$^{Z+}\\mu^-\\mu^-$ for Z=1 to 54. Convergence pattern of the energies have been checked with respect to the increasing number of partial waves $K_{max}$. For available computer facilities, calculations are feasible up to $K_{max}=28$ partial waves, however, calculation for still higher partial waves have been achieved through an appropriate extrapolation scheme. The dependence of bound state energies has been checked against increasing nuclear charge Z and finally, the calculated energies have been compared with the ones of the literature.
Casida, Mark E.; Jamorski, Christine; Casida, Kim C.; Salahub, Dennis R.
1998-03-01
This paper presents an evaluation of the performance of time-dependent density-functional response theory (TD-DFRT) for the calculation of high-lying bound electronic excitation energies of molecules. TD-DFRT excitation energies are reported for a large number of states for each of four molecules: N2, CO, CH2O, and C2H4. In contrast to the good results obtained for low-lying states within the time-dependent local density approximation (TDLDA), there is a marked deterioration of the results for high-lying bound states. This is manifested as a collapse of the states above the TDLDA ionization threshold, which is at -ɛHOMOLDA (the negative of the highest occupied molecular orbital energy in the LDA). The -ɛHOMOLDA is much lower than the true ionization potential because the LDA exchange-correlation potential has the wrong asymptotic behavior. For this reason, the excitation energies were also calculated using the asymptotically correct potential of van Leeuwen and Baerends (LB94) in the self-consistent field step. This was found to correct the collapse of the high-lying states that was observed with the LDA. Nevertheless, further improvement of the functional is desirable. For low-lying states the asymptotic behavior of the exchange-correlation potential is not critical and the LDA potential does remarkably well. We propose criteria delineating for which states the TDLDA can be expected to be used without serious impact from the incorrect asymptotic behavior of the LDA potential.
Semiclassical states on Lie algebras
Energy Technology Data Exchange (ETDEWEB)
Tsobanjan, Artur, E-mail: artur.tsobanjan@gmail.com [King’s College, 133 North River Street, Kingston, Pennsylvania 18702 (United States)
2015-03-15
The effective technique for analyzing representation-independent features of quantum systems based on the semiclassical approximation (developed elsewhere) has been successfully used in the context of the canonical (Weyl) algebra of the basic quantum observables. Here, we perform the important step of extending this effective technique to the quantization of a more general class of finite-dimensional Lie algebras. The case of a Lie algebra with a single central element (the Casimir element) is treated in detail by considering semiclassical states on the corresponding universal enveloping algebra. Restriction to an irreducible representation is performed by “effectively” fixing the Casimir condition, following the methods previously used for constrained quantum systems. We explicitly determine the conditions under which this restriction can be consistently performed alongside the semiclassical truncation.
Pugh, J. V.; Shen, K. K.; Winstead, C. B.; Gole, J. L.
1996-01-01
The first laser based probe for the sodium and lithium monoxides is established. The Li(Na)+N 2O reactions studied in a multiple collision entrainment mode produce the LiO and NaO ground X 2Π and low-lying monoxide excited states. In contrast to the alkali halides, laser induced excitation spectroscopy confirms that the LiO and NaO B 2Π states, counter to recent predictions, are located at energies well below the ground state dissociation asymptote and, as predicted, possess significant binding energies. An assignment of the laser induced excitation spectra (LIF) for the B 2Π-X 2Π transitions of LiO in the region 3940-4300 Å is based on a direct correlation with the observed chemiluminescence (CL) from the lowest level of the LiO B 2Π state ( ˜4000-7000 Å) and high quality ab initio calculations for the ground state. The self-consistent assignment of the observed LIF and CL spectra makes use of the complimentary extended progressions in the X 2Π (CL) and B 2Π (LIF) vibrational level structure which results from the significant shift of the B 2Π excited state potential relative to that of the ground state. The experimental data are consistent with an excited state vibrational frequency separation of order 130 cm -1, and T e( B2Π) ≈ 26078 ± 800 cm-1. The latter value, in correlation with the ground state dissociation energy of LiO, suggests a B 2Π excited state dissociation energy well in excess of 2000 cm -1. The radiative lifetimes of the lowest levels of the LiO B 2Π state, isoergic with the highest levels of the LiO ground state, are determined to be in excess of 600 ns. The corresponding NaO excitation spectra in the range 6680-7250 Å also correlate well with ab initio calculations for the ground electronic state of NaO. Within this study, we provide optical signatures which one might consider to monitor LiO or NaO in process streams. In correlation with the observed chemiluminescence from B 2Π states of the higher alkali oxides KO, RbO, and
Hoyer, Paul
2016-01-01
Even a first approximation of bound states requires contributions of all powers in the coupling. This means that the concept of "lowest order bound state" needs to be defined. In these lectures I discuss the "Born" (no loop, lowest order in $\\hbar$) approximation. Born level states are bound by gauge fields which satisfy the classical field equations. As a check of the method, Positronium states of any momentum are determined as eigenstates of the QED Hamiltonian, quantized at equal time. Analogously, states bound by a strong external field $A^\\mu(\\xv)$ are found as eigenstates of the Dirac Hamiltonian. Their Fock states have dynamically created $e^+e^-$ pairs, whose distribution is determined by the Dirac wave function. The linear potential of $D=1+1$ dimensions confines electrons but repels positrons. As a result, the mass spectrum is continuous and the wave functions have features of both bound states and plane waves. The classical solutions of Gauss' law are explored for hadrons in QCD. A non-vanishing bo...
DEFF Research Database (Denmark)
Faupin, Jeremy; Møller, Jacob Schach; Skibsted, Erik
2011-01-01
We study regularity of bound states pertaining to embedded eigenvalues of a self-adjoint operator H, with respect to an auxiliary operator A that is conjugate to H in the sense of Mourre. We work within the framework of singular Mourre theory which enables us to deal with confined massless Pauli–......–Fierz models, our primary example, and many-body AC-Stark Hamiltonians. In the simpler context of regular Mourre theory, our results boil down to an improvement of results obtained recently in [8, 9]....
Lying for the Greater Good: Bounded Rationality in a Team
Directory of Open Access Journals (Sweden)
Oktay Sürücü
2014-10-01
Full Text Available This paper is concerned with the interaction between fully and boundedly rational agents in situations where their interests are perfectly aligned. The cognitive limitations of the boundedly rational agent do not allow him to fully understand the market conditions and lead him to take non-optimal decisions in some situations. Using categorization to model bounded rationality, we show that the fully rational agent can nudge, i.e., he can manipulate the information he sends and decrease the expected loss caused by the boundedly rational agent. Assuming different types for the boundedly rational agent, who differ only in the categories used, we show that the fully rational agent may learn the type of the boundedly rational agent along their interaction. Using this additional information, the outcome can be improved and the amount of manipulated information can be decreased. Furthermore, as the length of the interaction increases the probability that the fully rational agent learns the type of the boundedly rational agent grows
Schulz, Marc Daniel; Dusuel, Sébastien; Vidal, Julien
2016-11-01
We discuss the emergence of bound states in the low-energy spectrum of the string-net Hamiltonian in the presence of a string tension. In the ladder geometry, we show that a single bound state arises either for a finite tension or in the zero-tension limit depending on the theory considered. In the latter case, we perturbatively compute the binding energy as a function of the total quantum dimension. We also address this issue in the honeycomb lattice where the number of bound states in the topological phase depends on the total quantum dimension. Finally, the internal structure of these bound states is analyzed in the zero-tension limit.
Schulz, M D; Vidal, J
2016-01-01
We discuss the emergence of bound states in the low-energy spectrum of the string-net Hamiltonian in the presence of a string tension. In the ladder geometry, we show that a single bound state arises either for a finite tension or in the zero-tension limit depending on the theory considered. In the latter case, we perturbatively compute the binding energy as a function of the total quantum dimension. We also address this issue in the honeycomb lattice where the number of bound states in the topological phase depends on the total quantum dimension. Finally, the internal structure of these bound states is analyzed in the zero-tension limit.
Nuclear internal conversion between bound atomic states
Chemin, J. F.; Harston, M. R.; Karpeshin, F. F.; Carreyre, J.; Attallah, F.; Aleonard, M. M.; Scheurer, J. N.; Boggaert, G.; Grandin, J. R.; Trzhaskovskaya, M. B.
2003-01-01
We present experimental and theoretical results for rate of decay of the (3/2)+ isomeric state in 125Te versus the ionic charge state. For charge state larger than 44 the nuclear transition lies below the threshold for emission of a K-shell electron into the continuum with the result that normal internal conversion is energetically forbiden. Rather surprisingly, for the charge 45 and 46 the lifetime of the level was found to have a value close to that in neutral atoms. We present direct evidence that the nuclear transition could still be converted but without the emission of the electron into the continuum, the electron being promoted from the K-shell to an other empty bound state lying close to the continuum. We called this process BIC. The experimental results agree whith theoretical calculations if BIC resonances are taken into account. This leads to a nuclear decay constant that is extremely sensitive to the precise initial state and simple specification of the charge state is no longer appropriate. The contribution to decay of the nucleus of BIC has recently been extended to the situation in which the electron is promoted to an intermediate filled bound state (PFBIC) with an apparent violation of the Pauli principle. Numerical results of the expected dependence of PFBIC on the charge state will be presented for the decay of the 77.351 keV level in 197Au.
Eta nuclear bound states revisited
Friedman, E; Mareš, J
2013-01-01
The strong energy dependence of the s-wave eta-N scattering amplitude at and below threshold, as evident in coupled-channels K-matrix fits and chiral models that incorporate the S11 N*(1535) resonance, is included self consistently in eta-nuclear bound state calculations. This approach, applied recently in calculations of kaonic atoms and Kbar-nuclear bound states, is found to impose stronger constraints than ever on the onset of eta-nuclear binding, with a minimum value of Re a_{eta N} approximately 0.9 fm required to accommodate an eta-4He bound state. Binding energies and widths of eta-nuclear states are calculated within several underlying eta-N models for nuclei across the periodic table, including eta-25Mg for which some evidence was proposed in a recent COSY experiment.
Wronskian Method for Bound States
Fernandez, Francisco M.
2011-01-01
We propose a simple and straightforward method based on Wronskians for the calculation of bound-state energies and wavefunctions of one-dimensional quantum-mechanical problems. We explicitly discuss the asymptotic behaviour of the wavefunction and show that the allowed energies make the divergent part vanish. As illustrative examples we consider…
Wronskian method for bound states
Energy Technology Data Exchange (ETDEWEB)
Fernandez, Francisco M, E-mail: fernande@quimica.unlp.edu.ar [INIFTA (UNLP, CONICET), Division Quimica Teorica, Boulevard 113 S/N, Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina)
2011-05-15
We propose a simple and straightforward method based on Wronskians for the calculation of bound-state energies and wavefunctions of one-dimensional quantum-mechanical problems. We explicitly discuss the asymptotic behaviour of the wavefunction and show that the allowed energies make the divergent part vanish. As illustrative examples we consider an exactly solvable model, the Gaussian potential well, and a two-well potential proposed earlier for the interpretation of the infrared spectrum of ammonia.
Bound entangled states invariant under Ux
Institute of Scientific and Technical Information of China (English)
Wang Zhen; Wang Zhi-Xi
2008-01-01
This paper obtains an entangled condition for isotropic-like states by using an atomic map. It constructs a class of bound entangled states from the entangled condition and shows that the partial transposition of the state from the constructed bound entangled class is an edge bound entangled state by using range criterion.
Boosting equal time bound states
Dietrich, Dennis D; Jarvinen, Matti
2012-01-01
We present an explicit and exact boost of a relativistic bound state defined at equal time of the constituents in the Born approximation (lowest order in hbar). To this end, we construct the Poincar\\'e generators of QED and QCD in D=1+1 dimensions, using Gauss' law to express A^0 in terms of the fermion fields in A^1=0 gauge. We determine the fermion-antifermion bound states in the Born approximation as eigenstates of the time and space translation generators P^0 and P^1. The boost operator is combined with a gauge transformation so as to maintain the gauge condition A^1=0 in the new frame. We verify that the boosted state remains an eigenstate of P^0 and P^1 with appropriately transformed eigenvalues and determine the transformation law of the equal-time, relativistic wave function. The shape of the wave function is independent of the CM momentum when expressed in terms of a variable, which is quadratically related to the distance x between the fermions. As a consequence, the Lorentz contraction of the wave ...
On the low-lying states of TiC
Bauschlicher, C. W., Jr.; Siegbahn, P. E. M.
1984-01-01
The ground and low-lying excited states of TiC are investigated using a CASSCF-externally contracted CI approach. The calculations yield a 3Sigma(+) ground state, but the 1Sigma(+) state is only 780/cm higher and cannot be ruled out. The low-lying states have some triple bond character. The nature of the bonding and origin of the states are discussed.
On the low-lying states of TiC
Bauschlicher, C. W., Jr.; Siegbahn, P. E. M.
1984-01-01
The ground and low-lying excited states of TiC are investigated using a CASSCF-externally contracted CI approach. The calculations yield a 3Sigma(+) ground state, but the 1Sigma(+) state is only 780/cm higher and cannot be ruled out. The low-lying states have some triple bond character. The nature of the bonding and origin of the states are discussed.
Asymmetric dark matter bound state
Bi, Xiao-Jun; Kang, Zhaofeng; Ko, P.; Li, Jinmian; Li, Tianjun
2017-02-01
We propose an interesting framework for asymmetric scalar dark matter (ADM), which has novel collider phenomenology in terms of an unstable ADM bound state (ADMonium) produced via Higgs portals. ADMonium is a natural consequence of the basic features of ADM: the (complex scalar) ADM is charged under a dark local U (1 )d symmetry which is broken at a low scale and provides a light gauge boson X . The dark gauge coupling is strong and then ADM can annihilate away into X -pair effectively. Therefore, the ADM can form a bound state due to its large self-interaction via X mediation. To explore the collider signature of ADMonium, we propose that ADM has a two-Higgs doublet portal. The ADMonium can have a sizable mixing with the heavier Higgs boson, which admits a large cross section of ADMonium production associated with b b ¯. The resulting signature at the LHC depends on the decays of X . In this paper we consider a case of particular interest: p p →b b ¯ +ADMonium followed by ADMonium→2 X →2 e+e- where the electrons are identified as (un)converted photons. It may provide a competitive explanation to heavy di-photon resonance searches at the LHC.
Hsu, Chia Wei; Zhen, Bo; Stone, A. Douglas; Joannopoulos, John D.; Soljačić, Marin
2016-09-01
Bound states in the continuum (BICs) are waves that remain localized even though they coexist with a continuous spectrum of radiating waves that can carry energy away. Their very existence defies conventional wisdom. Although BICs were first proposed in quantum mechanics, they are a general wave phenomenon and have since been identified in electromagnetic waves, acoustic waves in air, water waves and elastic waves in solids. These states have been studied in a wide range of material systems, such as piezoelectric materials, dielectric photonic crystals, optical waveguides and fibres, quantum dots, graphene and topological insulators. In this Review, we describe recent developments in this field with an emphasis on the physical mechanisms that lead to BICs across seemingly very different materials and types of waves. We also discuss experimental realizations, existing applications and directions for future work.
Bound anionic states of adenine
Energy Technology Data Exchange (ETDEWEB)
Haranczyk, Maciej; Gutowski, Maciej S; Li, Xiang; Bowen, Kit H
2007-03-20
Anionic states of nucleic acid bases are involved in DNA damage by low-energy electrons and in charge transfer through DNA. Previous gas phase studies of free, unsolvated nucleic acid base parent anions probed only dipole-bound states, which are not present in condensed phase environments, but did not observe valence anionic states, which for purine bases, are thought to be adiabatically unbound. Contrary to this expectation, we have demonstrated that some thus far ignored tautomers of adenine, which result from enamine-imine transformations, support valence anionic states with electron vertical detachment energies as large as 2.2 eV, and at least one of these anionic tautomers is adiabatically bound. Moreover, we predict that the new anionic tautomers should also dominate in solutions and should be characterized by larger values of electron vertical detachment energy than the canonical valence anion. All of the new-found anionic tautomers might be formed in the course of dissociative electron attachment followed by a hydrogen atom attachment to a carbon atom, and they might affect the structure and properties of DNA and RNA exposed to low-energy electrons. The discovery of these valence anionic states of adenine was facilitated by the development of: (i) a new experimental method for preparing parent anions of nucleic acid bases for photoelectron experiments, and (ii) a new combinatorial/ quantum chemical approach for identification of the most stable tautomers of organic molecules. The computational portion of this work was supported by the: (i) Polish State Committee for Scientific Research (KBN) Grants: DS/8000-4-0140-7 (M.G.) and N204 127 31/2963 (M.H.), (ii) European Social Funds (EFS) ZPORR/2.22/II/2.6/ARP/U/2/05 (M.H.), and (iii) US DOE Office of Biological and Environmental Research, Low Dose Radiation Research Program (M.G.). M.H. holds the Foundation for Polish Science (FNP) award for young scientists. The calculations were performed at the Academic
Mitchell, J P; Johnson, E D; Baby, L T; Kemper, K W; Moro, A M; Peplowski, P N; Volya, A; Wiedenhoever, I
2010-01-01
Excitation functions of elastic and inelastic 7Be+p scattering were measured in the energy range between 1.6 and 2.8 MeV in the c.m. An R-matrix analysis of the excitation functions provides strong evidence for new positive parity states in 8B. A new 2+ state at an excitation energy of 2.55 MeV was observed and a new 0+ state at 1.9 MeV is tentatively suggested. The R-matrix and Time Dependent Continuum Shell Model were used in the analysis of the excitation functions. The new results are compared to the calculations of contemporary theoretical models.
Instanton bound states in ABJM theory
Energy Technology Data Exchange (ETDEWEB)
Hatsuda, Yasuyuki [DESY Hamburg (Germany). Theory Group; Tokyo Institute of Technology (Japan). Dept. of Physics; Moriyama, Sanefumi [Nagoya Univ. (Japan). Kobayashi Maskawa Inst. and Graduate School of Mathematics; Okuyama, Kazumi [Shinshu Univ., Matsumoto, Nagano (Japan). Dept. of Physics
2013-06-15
The partition function of the ABJM theory receives non-perturbative corrections due to instanton effects. We study these non-perturbative corrections, including bound states of worldsheet instantons and membrane instantons, in the Fermi-gas approach. We require that the total non-perturbative correction should be always finite for arbitrary Chern-Simons level. This finiteness is realized quite non-trivially because each bound state contribution naively diverges at some levels. The poles of each contribution should be canceled out in total. We use this pole cancellation mechanism to find unknown bound state corrections from known ones. We conjecture a general expression of the bound state contribution. Summing up all the bound state contributions, we find that the effect of bound states is simply incorporated into the worldsheet instanton correction by a redefinition of the chemical potential in the Fermi-gas system. Analytic expressions of the 3- and 4-membrane instanton corrections are also proposed.
On the low lying singlet states of BeO
Bauschlicher, C. W., Jr.; Lengsfield, B. H.; Yarkony, D. R.
1980-01-01
Calculations of the ground and low-lying singlet states of BeO are performed in order to gain an understanding of the techniques needed to treat the excited states of other, more complex, ionic molecules. The MCSCF and CI calculations are based on a Gaussian basis set of slightly better than double zeta plus polarization quality for single configuration descriptions of the states. The calculated X-A and X-B state separations are found to be in agreement with experimental measurements. The 1 Sigma - and 1 Delta states are predicted to lie approximately 40,000 kaysers above the ground state and are identified as the C and D states.The 2 1 Pi state is found to be approximately 15,000 kaysers and the 3 1 Sigma + state is found to be approximately 65,000 kaysers above the ground state.
Internal conversion to bound final states in 125Te
Harston, M. R.; Carreyre, T.; Chemin, J. F.; Karpeshin, F.; Trzhaskovskaya, M. B.
2000-08-01
Theoretical results are presented for rate of decay of the 3/2+ isomeric nuclear state of 125Te by excitation of atomic electrons to bound states in the ions Te 45+ and Te 46+. In these ions the nuclear transition energy lies just below the threshold for emission of a K-shell electron to the continuum with the result that normal K-shell internal conversion is energetically forbidden. However recent experimental results indicate that excitation of K-shell electrons is still significant in these ions. The theoretical results presented here for internal conversion to bound final states are in quantitative agreement with experiment and thereby confirm the contribution of near-resonant electron-nucleus transitions involving a bound final state.
How entangled are bound entangled states?
Wei, T C; Goldbart, P M; Munro, W J; Wei, Tzu-Chieh; Altepeter, Joseph B.; Goldbart, Paul M.; Munro, William J.
2003-01-01
Bound entangled states are states that are entangled but from which no entanglement can be distilled if all parties are allowed only local operations and classical communication. However, in creating these states one needs nonzero entanglement to start with. To date, no analytic results reveal the entanglement content of these strange states. Here, the entanglement of two distinct multipartite bound entangled states is determined analytically in terms of geometric measure of entanglement and a related quantity. The results are compared with those for the relative entropy of entanglement and the negativity, and plausible lower bounds on the entanglement of formation are given. Along the way, an intriguing example emerges, in which a bipartite mixed state, associated with Smolin's bound entangled state, can be reversibly converted into a bipartite Bell state, and vice versa. Furthermore, for any N-qubit state that is PPT for all bipartite partitionings, there is no violation of the two-setting, three-setting, a...
Real weights, bound states and duality orbits
Marrani, Alessio; Romano, Luca
2015-01-01
We show that the duality orbits of extremal black holes in supergravity theories with symmetric scalar manifolds can be derived by studying the stabilizing subalgebras of suitable representatives, realized as bound states of specific weight vectors of the corresponding representation of the duality symmetry group. The weight vectors always correspond to weights that are real, where the reality properties are derived from the Tits-Satake diagram that identifies the real form of the Lie algebra of the duality symmetry group. Both N=2 magic Maxwell-Einstein supergravities and the semisimple infinite sequences of N=2 and N=4 theories in D=4 and 5 are considered, and various results, obtained over the years in the literature using different methods, are retrieved. In particular, we show that the stratification of the orbits of these theories occurs because of very specific properties of the representations: in the case of the theory based on the real numbers, whose symmetry group is maximally non-compact and there...
The low-lying electronic states of LiC
Ricca, Alessandra; Bauschlicher, Charles W., Jr.; Langhoff, Stephen R. (Technical Monitor)
1995-01-01
The spectroscopic constants for the doublet and quartet states of LiC below about 30,000/cm are determined using an internally contracted multireference configuration-interaction approach in conjunction with a [6s 5p 3d 2f] atomic natural orbital basis sets. All of the strongly bound states, X(sup 4)(SIGMA)(sup -),(1)(sup 2)(DELTA), (1)(sup 2)(SIGMA)(sup +), and (2)(sup 2) II, very ionic in character. The only bound-bound quartet transition in this energy range is (2)(sup 4)SIGMA(sup -) and Franck-Condon factors, Einstein A values, and lifetimes are reported for this transition.
The Low-Lying Electronic States of Mg2(+)
Ricca, Alessandra; Bauschlicher, Charles W., Jr.
1994-01-01
The low-lying doublet and quartet states of Mg+ have been studied using a multireference configuration interaction approach. The effect of inner-shell correlation has been included using the core-polarization potential method. The computed spectroscopic constants, lifetimes, and oscillator strengths should help resolve the difference between the recent experiments and previous theoretical calculations.
On the reflection of magnon bound states
MacKay, Niall
2010-01-01
We investigate the reflection of two-particle bound states of a free open string in the light-cone AdS_5 x S^5 string sigma model, for large angular momentum J=J_56 and ending on a D7 brane which wraps the entire AdS_5 and a maximal S^3 of S^5. We use the superspace formalism to analyse fundamental and two-particle bound states in the cases of supersymmetry-preserving and broken-supersymmetry boundaries. We find the boundary S-matrices corresponding to bound states both in the bulk and on the boundary.
Lower Bounds of Concurrence for Multipartite States
Zhu, Xue-Na; Fei, Shao-Ming
2012-01-01
We study the entanglement of multipartite quantum states. Some lower bounds of the multipartite concurrence are reviewed. We further present more effective lower bounds for detecting and qualifying entanglement, by establishing functional relations between the concurrence and the generalized partial transpositions of the multipartite systems.
Irreversibility for all bound entangled states
Yang, D; Horodecki, R; Synak-Radtke, B; Yang, Dong; Horodecki, Michal; Horodecki, Ryszard; Synak-Radtke, Barbara
2005-01-01
We derive a new inequality for entanglement for a mixed four-partite state. Employing this inequality, we present a one-shot lower bound for entanglement cost and prove that entanglement cost is strictly larger than zero for any entangled state. We demonstrate that irreversibility occurs in the process of formation for all non-distillable entangled states. In this way we solve a long standing problem, of how "real" is entanglement of bound entangled states. Using the new inequality we also prove impossibility of local-cloning and local-deleting of a known entangled state.
Bound States in Boson Impurity Models
Shi, Tao; Wu, Ying-Hai; González-Tudela, A.; Cirac, J. I.
2016-04-01
The formation of bound states involving multiple particles underlies many interesting quantum physical phenomena, such as Efimov physics or superconductivity. In this work, we show the existence of an infinite number of such states for some boson impurity models. They describe free bosons coupled to an impurity and include some of the most representative models in quantum optics. We also propose a family of wave functions to describe the bound states and verify that it accurately characterizes all parameter regimes by comparing its predictions with exact numerical calculations for a one-dimensional tight-binding Hamiltonian. For that model, we also analyze the nature of the bound states by studying the scaling relations of physical quantities, such as the ground-state energy and localization length, and find a nonanalytical behavior as a function of the coupling strength. Finally, we discuss how to test our theoretical predictions in experimental platforms, such as photonic crystal structures and cold atoms in optical lattices.
Ozone absorption spectroscopy in search of low-lying electronic states
Anderson, S. M.; Mauersberger, K.
1995-01-01
A spectrometer capable of detecting ozone absorption features 9 orders of magnitude weaker than the Hartley band has been employed to investigate the molecule's near-infrared absorption spectrum. At this sensitivity a wealth of information on the low-lying electronically excited states often believed to play a role in atmospheric chemistry is available in the form of vibrational and rotational structure. We have analyzed these spectra using a combination of digital filtering and isotope substitution and find evidence for three electronically excited states below 1.5 eV. The lowest of these states is metastable, bound by approximately 0.1 eV and probably the (3)A2 rather than the (3)B2 state. Its adiabatic electronic energy is 1.24 +/- 0.01 eV, slightly above the dissociation energy of the ground state. Two higher states, at 1.29 +/- 0.03 and 1.48 +/- 0.03 eV are identified as the (3)B2 and the (3)B1, respectively. Combined with other recent theoretical and experimental data on the low-lying electronic states of ozone, these results imply that these are, in fact, the lowest three excited states; that is, there are no electronically excited states of ozone lying below the energy of O(3P) + O2((3)Sigma(-), v = 0). Some of the implications for atmospheric chemistry are considered.
Family of nonlocal bound entangled states
Yu, Sixia; Oh, C. H.
2017-03-01
Bound entanglement, being entangled yet not distillable, is essential to our understanding of the relations between nonlocality and entanglement besides its applications in certain quantum information tasks. Recently, bound entangled states that violate a Bell inequality have been constructed for a two-qutrit system, disproving a conjecture by Peres that bound entanglement is local. Here we construct this kind of nonlocal bound entangled state for all finite dimensions larger than two, making possible their experimental demonstration in most general systems. We propose a Bell inequality, based on a Hardy-type argument for nonlocality, and a steering inequality to identify their nonlocality. We also provide a family of entanglement witnesses to detect their entanglement beyond the Bell inequality and the steering inequality.
η-nuclear bound states revisited
Friedman, E.; Gal, A.; Mareš, J.
2013-10-01
The strong energy dependence of the s-wave ηN scattering amplitude at and below threshold, as evident in coupled-channels K-matrix fits and chiral models that incorporate the S11N* (1535) resonance, is included self-consistently in η-nuclear bound-state calculations. This approach, applied recently in calculations of kaonic atoms and Kbar-nuclear bound states, is found to impose stronger constraints than ever on the onset of η-nuclear binding, with a minimum value of ReaηN ≈ 0.9 fm required to accommodate an η-4He bound state. Binding energies and widths of η-nuclear states are calculated within several underlying ηN models for nuclei across the periodic table, including Mg25η for which some evidence was proposed in a recent COSY experiment.
Narrow deeply bound K- atomic states
Friedman, E.; Gal, A.
1999-07-01
Using optical potentials fitted to a comprehensive set of strong interaction level shifts and widths in K- atoms, we predict that the K- atomic levels which are inaccessible in the atomic cascade process are generally narrow, spanning a range of widths about 50-1500 keV over the entire periodic table. The mechanism for this narrowing is different from the mechanism for narrowing of pionic atom levels. Examples of such `deeply bound' K- atomic states are given, showing that in many cases these states should be reasonably well resolved. Several reactions which could be used to form these `deeply bound' states are mentioned. Narrow deeply bound states are expected also in overlinep atoms.
Introduction to QCD - a bound state perspective
Hoyer, Paul
2011-01-01
These lecture notes focus on the bound state sector of QCD. Motivated by data which suggests that the strong coupling \\alpha_s(Q) freezes at low Q, and by similarities between the spectra of hadrons and atoms, I discuss if and how QCD bound states may be treated perturbatively. I recall the basic principles of perturbative gauge theory bound states at lowest order in the \\hbar expansion. Born level amplitudes are insensitive to the i\\epsilon prescription of propagators, which allows to eliminate the Z-diagrams of relativistic, time-ordered Coulomb interactions. The Dirac wave function thus describes a single electron which propagates forward in time only, even though the bound state has any number of pair constituents when Feynman propagators are used. In the absence of an external potential, states that are bound by the Coulomb attraction of their constituents can be analogously described using only their valence degrees of freedom. The instantaneous A^0 field is determined by Gauss' law for each wave functi...
Bound States Of Supersymmetric Black Holes
Britto-Pacumio, R A
2002-01-01
The quantum mechanics of N slowly-moving supersymmetric black holes in five dimensions is considered. A divergent continuum of states describing arbitrarily closely bound black holes with arbitrarily small excitation energies is found. A superconformal structure appears at low energies and can be used to define a topological index counting the weighted number of supersymmetric bound states. It is shown that the index is determined from the dimensions of certain cohomology classes on the symmetric product of N copies of R4. This bound state index is computed exactly for two and three black holes. The required regulator for the infrared continuum of near-coincident black holes is chosen in accord with the enhanced superconformal symmetry.
On the low-lying states of CuO
Bagus, P. S.; Nelin, C. J.; Bauschlicher, C. W., Jr.
1984-01-01
Self consistent field and correlated wave functions have been computed for the ground and for several low-lying states of CuO. The ground state is X(2)PI and the lowest excited state, at approximately 8,000/cm above X(2)PI, is a previously unidentified 2-sigma(+) state. The separation of these states is compared to that for the similar states of KO and is analysed in terms of integrals between orbitals of the separated free ions. A classification of the states of the molecule based on states of Cu(+) and O(-) which leads to a division into manifolds of states arising from Cu(+) 3d(10) and Cu(+) 3d(9) 4s(1) is considered. It is predicted that the state of the 3d(9) 4s(1) manifold are 10,000 to 30,000/cm above the ground state and assign the observed A2-sigma(+) state at 16,500/cm to this manifold.
Low lying charmonium states at the physical point
Mohler, Daniel; Kronfeld, Andreas S; Lee, Song-haeng; Levkova, Ludmila; Simone, J N
2014-01-01
We present results for the mass splittings of low-lying charmonium states from a calculation with Wilson clover valence quarks with the Fermilab interpretation on an asqtad sea. We use five lattice spacings and two values of the light sea quark mass to extrapolate our results to the physical point. Sources of systematic uncertainty in our calculation are discussed and we compare our results for the 1S hyperfine splitting, the 1P-1S splitting and the P-wave spin orbit and tensor splittings to experiment.
Radiative Decays of Low-Lying Excited-State Hyperons
Energy Technology Data Exchange (ETDEWEB)
Taylor, Simon [Rice Univ., Houston, TX (United States)
2000-05-01
The quark wave-functions of the lower-lying excited-state hyperons Lambda(1405), Sigma(1385), and Lambda(1520) are not well understood. For example, the Lambda(1405) may not be a regular three-quark state but a $\\bar{K}$N molecule. Several competing models have been proposed, but none have been convincingly eliminated. Measuring radiative decays provides a means of discriminating between the models. The radiative branching of ratios are predicted to be small (~1%), but the radiative widths vary by factors of 2-10 from model to model. The existing experimental data is sparse and inconsistent; moreover, the radiative decay of the Sigma(1385) has never been observed before (except for one event). These lower-lying excited state hypersons were produced in a tagged photon-beam experiment in the CLAS detector at TJNAF in the reaction gamma p → K^{+} Y* for photon energies from threshold to 2.4 GeV. The radiative branching ration for the Sigma^{0}(1385) relative to the Sigma^{0}(1385) → Lambda pi^{0} channel was measured to be 0.021 ± 0.008$+0.004\\atop{-0.007}$, corresponding to a partial width of 640 ± 270$+130\\atop{-220}$ keV.
A New Approach to Solve the Low-lying States of the Schroedinger Equation
Lee Tsung Dao
2005-01-01
We review a new iterative procedure to solve the low-lying states of the Schroedinger equation, done in collaboration with Richard Friedberg. For the groundstate energy, the $n^{th}$ order iterative energy is bounded by a finite limit, independent of $n$; thereby it avoids some of the inherent difficulties faced by the usual perturbative series expansions. For a fairly large class of problems, this new procedure can be proved to give convergent iterative solutions. These convergent solutions include the long standing difficult problem of a quartic potential with either symmetric or asymmetric minima.
Analytic continuation of bound states to solve resonance states
Energy Technology Data Exchange (ETDEWEB)
Tanaka, Norimichi; Arai, Koji [Niigata Univ. (Japan); Suzuki, Yoshiyuki; Varga, K.
1997-05-01
As a method to determine the parameters of the resonance state, a method is proposed using analytic continuation on bound constants of correlation. The characteristics of this method consists in probability of prediction of the parameters of the resonance state only by calculation of the bound state. Owing to conducting the analytic continuation on square root of energy in the bound state as a function relating to the bound constant, energy and width in the bound state was determined. Here was reported on a result of application of this method to three systems. Some partial wave on two systems showing correlation at a simple potential and a resonance state of zero of all orbital angular motion quality in three boson system were determined using the analytic continuation method. These results agreed well with one used a method of integrating Schroedinger equation directly and one used the complex scaling method, and this method was found to be much efficient for the study of the resonance state. Under a background of becoming applicable to the method of analytic continuation, there was development of calculating method for the recent small number multi system. As the characteristics of the analytic continuation method is used for only calculation of the bound state, it is convenient at a point applicable to the method to obtain conventional bound state and then is much efficient in a point of applicability of calculus of variations. However, in order to obtain coefficient of Pade approximation correctly, the bound state must be solved correctly, which is difficult for more complex system and is not always applicable to every systems. (G.K.)
Low-Lying States of the A+B-A+B- Coulomb Systems in Two-Dimensional Quantum Dots
Institute of Scientific and Technical Information of China (English)
XIE Wen-Fang
2001-01-01
The features of the low-lying spectra of four-body A+B-A+B- systems have been deduced based on symmetry. Using the method of few-body physics, we calculate the energy spectra of A + B- A + B- systems in a harmonic quantum dot. We find that the biexciton in a two-dimensional quantum dot may have other bound excited states and the quantum mechanical symmetry plays a crucialrole in determining the energy levels and structures of the low-lying states.
Andreev bound states. Some quasiclassical reflections
Energy Technology Data Exchange (ETDEWEB)
Lin, Y., E-mail: yiriolin@illinois.edu; Leggett, A. J. [University of Illinois at Urhana-Champaign, Dept. of Physics (United States)
2014-12-15
We discuss a very simple and essentially exactly solvable model problem which illustrates some nice features of Andreev bound states, namely, the trapping of a single Bogoliubov quasiparticle in a neutral s-wave BCS superfluid by a wide and shallow Zeeman trap. In the quasiclassical limit, the ground state is a doublet with a splitting which is proportional to the exponentially small amplitude for “normal” reflection by the edges of the trap. We comment briefly on a prima facie paradox concerning the continuity equation and conjecture a resolution to it.
Nuclear dynamics of K¯ bound states
Mareš, J.; Friedman, E.; Gal, A.
2006-07-01
K¯ nuclear bound states were generated dynamically within a relativistic mean field (RMF) model. Substantial polarization of the core nucleus was found for light nuclei. The behavior of the dynamically calculated width ΓK¯ as function of the K¯ binding energy was studied. A lower limit of ΓK¯ ˜ 35 - 45 MeV for 1s K¯ nuclear states in light nuclei such as 12C was placed on the width expected for deep binding in the range B K¯ ˜ 100 - 200 MeV.
Ndangali, Friends R
2010-01-01
Electromagnetic bound states in the radiation continuum are studied for periodic double arrays of subwavelength dielectric cylinders in TM polarization. They are similar to localized waveguide mode solutions of Maxwell's equations for metal cavities or defects of photonic crystals, but, in contrast to the latter, their spectrum lies in the radiation continuum. The phenomenon is identical to the existence of bound sates in the radiation continuum in quantum mechanics, discovered by von Neumann and Wigner. In the formal scattering theory, these states appear as resonances with the vanishing width. For the system studied, the bound states are shown to exist at specific distances between the arrays in the spectral region where one or two diffraction channels are open. Analytic solutions are obtained for all bound states (below the radiation continuum and in it) in the limit of thin cylinders (the cylinder radius is much smaller than the wavelength). The existence of bound states is also established in the spectra...
Deceptive Intentions: Can Cues to Deception Be Measured before a Lie Is Even Stated?
National Research Council Canada - National Science Library
Ströfer, S; Noordzij, Matthijs L; Ufkes, E.G; Giebels, Ellen
2015-01-01
.... Both are related to increased sympathetic nervous system (SNS) activity. We hypothesized that SNS activity already rises during intentions to lie and, consequently, cues to deception can be detected before stating an actual lie...
Deceptive Intentions: Can Cues to Deception Be Measured before a Lie Is Even Stated?: e0125237
National Research Council Canada - National Science Library
Sabine Ströfer; Matthijs L Noordzij; Elze G Ufkes; Ellen Giebels
2015-01-01
.... Both are related to increased sympathetic nervous system (SNS) activity. We hypothesized that SNS activity already rises during intentions to lie and, consequently, cues to deception can be detected before stating an actual lie...
Is there an quasi-bound state?
Wilkin, C; Chiladze, D; Dymov, S; Hanhart, C; Hartmann, M; Hejny, V; Kacharava, A K; Keshelashvili, I; Khoukaz, A; Maeda, Y; Mersmann, T; Mielke, M; Mikirtychiants, S; Papenbrock, M; Rathmann, F; Rausmann, T; Schleichert, R; Ströher, H; Täschner, A; Valdau, Yu; Wronska, A
2007-01-01
The observed variation of the total cross section for the dp -> 3He eta reaction near threshold means that the magnitude of the s--wave amplitude falls very rapidly with the eta centre--of--mass momentum. It is shown here that recent measurements of the momentum dependence of the angular distribution imply a strong variation also in the phase of this amplitude. Such a behaviour is that expected from a quasi--bound or virtual eta-3He state. The interpretation can be investigated further through measurements of the deuteron or proton analysing powers and/or spin--correlations.
Novel Bound States in Graphene with Impurities
Gupta, Kumar S
2008-01-01
We obtain a novel bound state spectrum of the low energy excitations near the Fermi points of graphene in the presence of a charge impurity. The effects of possible short range interactions induced by the impurity are modelled by suitable boundary conditions. The spectrum in the subcritical region of the effective Coulomb coupling is labelled by a parameter which characterizes the boundary conditions and determines the inequivalent quantizations of the system. In the supercritical region we obtain a renormalization group flow for the effective Coulomb coupling.
Engineering the coupling between Majorana bound states
Shi, Z. C.; Shao, X. Q.; Xia, Y.; Yi, X. X.
2017-09-01
We study the coupling between Majorana bound states (CMBS), which is mediated by a topologically trivial chain in the presence of pairing coupling and long-range coupling. The results show that CMBS can be enhanced by the pairing coupling and long-range coupling of the trivial chain. When driving the trivial chain by periodic driving field, we deduce the analytical expressions of CMBS in the high-frequency limit, and demonstrate that CMBS can be modulated by the frequency and amplitude of driving field. Finally we exhibit the application of tunable CMBS in realizing quantum logic gates.
Fermionic bound states in distinct kinklike backgrounds
Energy Technology Data Exchange (ETDEWEB)
Bazeia, D. [Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, Paraiba (Brazil); Mohammadi, A. [Universidade Federal de Campina Grande, Departamento de Fisica, Caixa Postal 10071, Campina Grande, Paraiba (Brazil)
2017-04-15
This work deals with fermions in the background of distinct localized structures in the two-dimensional spacetime. Although the structures have a similar topological character, which is responsible for the appearance of fractionally charged excitations, we want to investigate how the geometric deformations that appear in the localized structures contribute to the change in the physical properties of the fermionic bound states. We investigate the two-kink and compact kinklike backgrounds, and we consider two distinct boson-fermion interactions, one motivated by supersymmetry and the other described by the standard Yukawa coupling. (orig.)
Bound states -- from QED to QCD
Hoyer, Paul
2014-01-01
These lectures are divided into two parts. In Part 1 I discuss bound state topics at the level of a basic course in field theory: The derivation of the Schr\\"odinger and Dirac equations from the QED Lagrangian, by summing Feynman diagrams and in a Hamiltonian framework. Less well known topics include the equal-time wave function of Positronium in motion and the properties of the Dirac wave function for a linear potential. The presentation emphasizes physical aspects and provides the framework for Part 2, which discusses the derivation of relativistic bound states at Born level in QED and QCD. A central aspect is the maintenance of Poincar\\'e invariance. The transformation of the wave function under boosts is studied in detail in D=1+1 dimensions, and its generalization to D=3+1 is indicated. Solving Gauss' law for $A^0$ with a non-vanishing boundary condition leads to a linear potential for QCD mesons, and an analogous confining potential for baryons.
On Aharonov-Casher bound states
Silva, E. O.; Andrade, F. M.; Filgueiras, C.; Belich, H.
2013-04-01
In this work bound states for the Aharonov-Casher problem are considered. According to Hagen's work on the exact equivalence between spin-1/2 Aharonov-Bohm and Aharonov-Casher effects, is known that the ∇ṡ E term cannot be neglected in the Hamiltonian if the spin of particle is considered. This term leads to the existence of a singular potential at the origin. By modeling the problem by boundary conditions at the origin which arises by the self-adjoint extension of the Hamiltonian, we derive for the first time an expression for the bound state energy of the Aharonov-Casher problem. As an application, we consider the Aharonov-Casher plus a two-dimensional harmonic oscillator. We derive the expression for the harmonic oscillator energies and compare it with the expression obtained in the case without singularity. At the end, an approach for determination of the self-adjoint extension parameter is given. In our approach, the parameter is obtained essentially in terms of physics of the problem.
On Aharonov-Casher bound states
Energy Technology Data Exchange (ETDEWEB)
Silva, E.O. [Universidade Federal do Maranhao, Departamento de Fisica, Sao Luis, MA (Brazil); Andrade, F.M. [Universidade Estadual de Ponta Grossa, Departamento de Matematica e Estatistica, Ponta Grossa, PR (Brazil); Filgueiras, C. [Universidade Federal de Campina Grande, Departamento de Fisica, Caixa Postal 10071, Campina Grande, PB (Brazil); Belich, H. [Universidade Federal do Espirito Santo, Departamento de Fisica e Quimica, Vitoria, ES (Brazil)
2013-04-15
In this work bound states for the Aharonov-Casher problem are considered. According to Hagen's work on the exact equivalence between spin-1/2 Aharonov-Bohm and Aharonov-Casher effects, is known that the {nabla}.E term cannot be neglected in the Hamiltonian if the spin of particle is considered. This term leads to the existence of a singular potential at the origin. By modeling the problem by boundary conditions at the origin which arises by the self-adjoint extension of the Hamiltonian, we derive for the first time an expression for the bound state energy of the Aharonov-Casher problem. As an application, we consider the Aharonov-Casher plus a two-dimensional harmonic oscillator. We derive the expression for the harmonic oscillator energies and compare it with the expression obtained in the case without singularity. At the end, an approach for determination of the self-adjoint extension parameter is given. In our approach, the parameter is obtained essentially in terms of physics of the problem. (orig.)
A balance for Dark Matter bound states
Nozzoli, F
2016-01-01
Massive particles with self interactions of the order of 0.2 barn/GeV are intriguing Dark Matter candidates from an astrophysical point of view. Direct detection searches for very massive particles, with relatively high cross sections with ordinary matter, cannot rule out $\\sigma/M > 0.01$ barn/GeV, due to atmosphere and material shielding. Here, the possibility of the existence of bound states with ordinary matter, for Dark Matter candidates with not negligible interactions, is considered. The existence of bound states, with binding energy larger than $\\sim$1 meV, would offer the possibility to test in laboratory capture cross sections of the order of a barn (or larger). The signature of the detection of a mass increasing of cryogenic samples, due to the possible Dark Matter accumulation, would allow the investigation of Dark Matter particles with mass up to the GUT scale. A proof of concept for a possible detection set-up and the evaluation of some noise sources are described.
ADMonium: Asymmetric Dark Matter Bound State
Bi, Xiao-Jun; Ko, P; Li, Jinmian; Li, Tianjun
2016-01-01
We propose a novel framework for asymmetric scalar dark matter (ADM), which has interesting collider phenomenology in terms of an unstable ADM bound state (ADMonium) produced via Higgs portals. ADMonium is a natural consequence of the basic features of ADM: the (complex scalar) ADM is charged under a dark local $U(1)_d$ symmetry which is broken at a low scale and provides a light gauge boson $X$. The dark gauge coupling is strong and then ADM can annihilate away into $X$-pair effectively. Therefore, the ADM can form bound state due to its large self-interaction via $X$ mediation. To explore the collider signature of ADMonium, we propose that ADM has a two-Higgs doublet portal. The ADMonium can have a sizable mixing with the heavier Higgs boson, which admits a large cross section of ADMonium production associated with $b\\bar b$. Of particular interest, our setup nicely explains the recent di-photon anomaly at 750 GeV via the events from ${\\rm ADMonium}\\ra 2X(\\ra e^+e^-)$, where the electrons are identified as ...
The H2+ molecular ion: Low-lying states
Olivares-Pilón, Horacio; Turbiner, Alexander V.
2016-10-01
Matching for a wavefunction the WKB expansion at large distances and Taylor expansion at small distances leads to a compact, few-parametric uniform approximation found in Turbiner and Olivares-Pilon (2011). The ten low-lying eigenstates of H2+ of the quantum numbers (n , m , Λ , ±) with n = m = 0 at Λ = 0 , 1 , 2, with n = 1, m = 0 and n = 0, m = 1 at Λ = 0 of both parities are explored for all interproton distances R. For all these states this approximation provides the relative accuracy ≲ 10-5 (not less than 5 s.d.) locally, for any real coordinate x in eigenfunctions, when for total energy E(R) it gives 10-11 s.d. for R ∈ [ 0 , 50 ] a.u. Corrections to the approximation are evaluated in the specially-designed, convergent perturbation theory. Separation constants are found with not less than 8 s.d. The oscillator strength for the electric dipole transitions E 1 is calculated with not less than 6 s.d. A dramatic dip in the E 1 oscillator strength f 1 sσg - 3 pσu at R ∼Req is observed. The magnetic dipole and electric quadrupole transitions are calculated for the first time with not less than 6 s.d. in oscillator strength. For two lowest states (0 , 0 , 0 , ±) (or, equivalently, 1 sσg and 2 pσu states) the potential curves are checked and confirmed in the Lagrange mesh method within 12 s.d. Based on them the Energy Gap between 1 sσg and 2 pσu potential curves is approximated with modified Pade Re-R [ Pade(8 / 7) ] (R) with not less than 4-5 figures at R ∈ [ 0 , 40 ] a.u. Sum of potential curves E1sσg +E2pσu is approximated by Pade 1 / R [ Pade(5 / 8) ] (R) in R ∈ [ 0 , 40 ] a.u. with not less than 3-4 figures.
Hyperquarks and bosonic preon bound states
Schmid, Michael L.; Buchmann, Alfons J.
2009-11-01
In a model in which leptons, quarks, and the recently introduced hyperquarks are built up from two fundamental spin-(1)/(2) preons, the standard model weak gauge bosons emerge as preon bound states. In addition, the model predicts a host of new composite gauge bosons, in particular, those responsible for hyperquark and proton decay. Their presence entails a left-right symmetric extension of the standard model weak interactions and a scheme for a partial and grand unification of nongravitational interactions based on, respectively, the effective gauge groups SU(6)P and SU(9)G. This leads to a prediction of the Weinberg angle at low energies in good agreement with experiment. Furthermore, using evolution equations for the effective coupling strengths, we calculate the partial and grand unification scales, the hyperquark mass scale, as well as the mass and decay rate of the lightest hyperhadron.
Hyperquarks and bosonic preon bound states
Schmid, Michael L
2013-01-01
In a model in which leptons, quarks, and the recently introduced hyperquarks are built up from two fundamental spin 1/2 preons, the standard model weak gauge bosons emerge as preon bound states. In addition, the model predicts a host of new composite gauge bosons, in particular those responsible for hyperquark and proton decay. Their presence entails a left-right symmetric extension of the standard model weak interactions and a scheme for a partial and grand unification of nongravitational interactions based on respectively the effective gauge groups SU(6)_P and SU(9)_G. This leads to a prediction of the Weinberg angle at low energies in good agreement with experiment. Furthermore, using evolution equations for the effective coupling strengths, we calculate the partial and grand unification scales, the hyperquark mass scale, as well as the mass and decay rate of the lightest hyperhadron.
Topological magnon bound-states in quantum Heisenberg chains
Qin, Xizhou; Ke, Yongguan; Zhang, Li; Lee, Chaohong
2016-01-01
It is still an outstanding challenge to characterize and understand the topological features of strongly correlated states such as bound-states in interacting multi-particle quantum systems. Recently, bound states of elementary spin waves (magnons) in quantum magnets have been experimentally observed in quantum Heisenberg chains comprising ultracold Bose atoms in optical lattices. Here, we explore an unprecedented topological state called topological magnon bound-state in the quantum Heisenberg chain under cotranslational symmetry. We find that the cotranslational symmetry allows us to formulate a direct topological invariant for the multi-particle quantum states, which can be used to characterize the topological features of multi-magnon excitations. We calculate energy spectra, density distributions, correlations and topological invariants of the two-magnon bound-states and show the existence of topological magnon bound-states. Our study not only opens a new prospect to pursue topological bound-states, but a...
Low-lying electronic states of CuN calculated by MRCI method
Zhang, Shu-Dong; Liu, Chao
2016-10-01
The high accuracy ab initio calculation method of multi-reference configuration interaction (MRCI) is used to compute the low-lying eight electronic states of CuN. The potential energy curves (PECs) of the X3Σ-, 13Π, 23Σ-, 13Δ, 11Δ, 11Σ-, 11Π, and 5Σ- in a range of R = 0.1 nm-0.5 nm are obtained and they are goodly asymptotes to the Cu(2Sg) + N(4Su) and Cu(2Sg) + N(2Du) dissociation limits. All the possible vibrational levels, rotational constants, and spectral constants for the six bound states of X3Σ-, 13Π, 23Σ-, 11Δ, 11Σ-, and 11Π are obtained by solving the radial Schrödinger equation of nuclear motion with the Le Roy provided Level8.0 program. Also the transition dipole moments from the ground state X3Σ- to the excited states 13Π and 23Σ- are calculated and the result indicates that the 23Σ--X3Σ- transition has a much higher transition dipole moment than the 13Π-X3Σ- transition even though the 13Π state is much lower in energy than the 23Σ- state.
Microscopic Description of Low-Lying Isovector Quadrupole States in /sup 56/Fe
Energy Technology Data Exchange (ETDEWEB)
Nikolaeva, R.; Stoyanov, C.; Vdovin, A.I.
1989-01-01
Microscopic calculations of energies, structure and transition probabilities of low-lying 2/sup +/ states in /sup 56/Fe have been performed in the framework of the quasi-particle phonon nuclear model. The interaction of the phonons appears to play an important role in determination of the isotopic character of low-lying quadrupole states.
Noncollisional excitation of low-lying states in gaseous nebulae
Rubin, Robert H.
1986-01-01
Consideration is given to the effects of processes other than electron collisional excitation on the energy level populations of species of C, N, and O. It is found that dielectronic as well as direct-radiative recombination may contribute significantly and in some cases be the major input to populating the low-lying metastable levels. It is concluded that the most pronounced changes occur when there is a large effective recombination coefficient to a level and when T(e) is low. The most dramatic change among the forbidden lines occurs for the O II forbidden lines.
Precision Study of Positronium: Testing Bound State QED Theory
Karshenboim, Savely G.
2003-01-01
As an unstable light pure leptonic system, positronium is a very specific probe atom to test bound state QED. In contrast to ordinary QED for free leptons, the bound state QED theory is not so well understood and bound state approaches deserve highly accurate tests. We present a brief overview of precision studies of positronium paying special attention to uncertainties of theory as well as comparison of theory and experiment. We also consider in detail advantages and disadvantages of positro...
Review of the N-quantum Approach to Bound States
Greenberg, O W
2010-01-01
We describe a method of solving quantum field theories using operator techniques based on the expansion of interacting fields in terms of asymptotic fields. For bound states, we introduce an asymptotic field for each (stable) bound state. We choose the nonrelativistic hydrogen atom as an example to illustrate the method. Future work will apply this N-quantum approach to relativistic theories that include bound states in motion.
The Low-Lying Electronic States of LiB
Ricca, Alessandra; Bauschlicher, Charles W., Jr.; Langhoff, Stephen R. (Technical Monitor)
1995-01-01
The spectroscopic constants for the triplet and singlet states of LiB below about 30 000/ cm are determined using an internally contracted multireference configuration interaction approach in conjunction with [6s 5p 3d 2f] atomic natural orbital basis sets. The ground state is (sup 3)Pi as found in previous work. No excited triplet states are found to be ideal for characterizing the ground state; the (1)(sup 3)Sigma(sup -) state has a transition energy that is too small for many experimental approaches and the (2)(sup 3)Pi and (3)(sup 3)Pi states have bond lengths that are significantly longer than the ground state, resulting in transition intensities that are spread out over many vibrational levels of the ground state.
On the low-lying states of TiN
Bauschlicher, C. W., Jr.
1983-01-01
A series of CAS SCF and multi-reference CI calculations are used to describe the lowest states of TiN. The bonding in all states is described as a triple bond involving the Ti 3d orbitals. The system has some ionic character as seen from both population analysis and dipole moment. The origins of the excited states are discussed.
Deceptive Intentions: Can Cues to Deception Be Measured before a Lie Is Even Stated?
Ströfer, Sabine; Noordzij, Matthijs L.; Ufkes, Elze G.; Giebels, Ellen
2015-01-01
Can deceitful intentions be discriminated from truthful ones? Previous work consistently demonstrated that deceiving others is accompanied by nervousness/stress and cognitive load. Both are related to increased sympathetic nervous system (SNS) activity. We hypothesized that SNS activity already rises during intentions to lie and, consequently, cues to deception can be detected before stating an actual lie. In two experiments, controlling for prospective memory, we monitored SNS activity during lying, truth telling, and truth telling with the aim of lying at a later instance. Electrodermal activity (EDA) was used as an indicator of SNS. EDA was highest during lying, and compared to the truth condition, EDA was also raised during the intention to deceive. Moreover, the switch from truth telling toward lying in the intention condition evoked higher EDA than switching toward non-deception related tasks in the lie or truth condition. These results provide first empirical evidence that increased SNS activity related to deception can be monitored before a lie is stated. This implies that cues to deception are already present during the mere intention to lie. PMID:26018573
Bound states in a hyperbolic asymmetric double-well
Energy Technology Data Exchange (ETDEWEB)
Hartmann, R. R., E-mail: richard.hartmann@dlsu.edu.ph [Physics Department, De La Salle University, 2401 Taft Avenue, Manila (Philippines)
2014-01-15
We report a new class of hyperbolic asymmetric double-well whose bound state wavefunctions can be expressed in terms of confluent Heun functions. An analytic procedure is used to obtain the energy eigenvalues and the criterion for the potential to support bound states is discussed.
Relativistic bound-state equations for fermions with instantaneous interactions
Suttorp, L.G.
1979-01-01
Three types of relativistic bound-state equations for a fermion pair with instantaneous interaction are studied, viz., the instantaneous Bethe-Salpeter equation, the quasi-potential equation, and the two-particle Dirac equation. General forms for the equations describing bound states with arbitrary
Asymptotic-bound-state model for Feshbach resonances
Tiecke, T.G.; Goosen, M.R.; Walraven, J.T.M.; Kokkelmans, S.J.J.M.F.
2010-01-01
We present an asymptotic-bound-state model which can be used to accurately describe all Feshbach resonance positions and widths in a two-body system. With this model we determine the coupled bound states of a particular two-body system. The model is based on analytic properties of the two-body
The Low-Lying Electronic States of YCu
Ricca, Alessandra; Bauschlicher, Charles W., Jr.; Langhoff, Stephen R. (Technical Monitor)
1995-01-01
The spectroscopic constants for the singlet and triplet states of YCu below about 15 000 per centimeter are determined using an internally contracted multireference configuration-interaction approach. These calculations are calibrated by studies of fewer states using higher levels of correlation treatment and/or larger basis sets. The computed T(sub e) values and radiative lifetimes are in reasonable agreement with experiment. The calculations confirm the previous experimental assignment for all but one state, where theory helps resolve between two possible assignments.
Theoretical Study of the Low-Lying States of MgN+2
Maitre, Philippe; Bauschlicher, Charles W., Jr.; Gross, Anthony R. (Technical Monitor)
1994-01-01
The structure and binding energies of the low-lying states of MgN2+ have been computed at the multireference configuration interaction level of theory. The effect of Mg inner-shell correlation have been included using the core-polarization potential method. The charge-quadrupole interaction results in a linear 2Sigma+ ground state as expected. The excited states can arise from either the interaction of the 2-P state of Mg+ with N2 or from charge transfer states with Mg(sup 2+)N2- bonding character. The lowest lying excited state, 2-B2, is mixture of these two mechanisms, which results in a C2v, geometry with Mg atoms sitting at the N2 bond midpoint. The small barrier in the bending potential exists between this state and the 2-II State which is the lowest lying linear excited state.
Low-Lying ππ* States of Heteroaromatic Molecules: A Challenge for Excited State Methods.
Prlj, Antonio; Sandoval-Salinas, María Eugenia; Casanova, David; Jacquemin, Denis; Corminboeuf, Clémence
2016-06-14
The description of low-lying ππ* states of linear acenes by standard electronic structure methods is known to be challenging. Here, we broaden the framework of this problem by considering a set of fused heteroaromatic rings and demonstrate that standard electronic structure methods do not provide a balanced description of the two (typically) lowest singlet state (La and Lb) excitations. While the Lb state is highly sensitive to correlation effects, La suffers from the same drawbacks as charge transfer excitations. We show that the comparison between CIS/CIS(D) can serve as a diagnostic for detecting the two problematic excited states. Standard TD-DFT and even its spin-flip variant lead to inaccurate excitation energies and interstate gaps, with only a double hybrid functional performing somewhat better. The complication inherent to a balanced description of these states is so important that even CC2 and ADC(2) do not necessarily match the ADC(3) reference.
Ultrarelativistic bound states in the shallow spherical well
Zaba, Mariusz
2016-01-01
We determine approximate eigenvalues and eigenfunctions shapes for bound states in the $3D$ shallow spherical ultrarelativistic well. Existence thresholds for the ground state and first excited states are identified, both in the purely radial and orbitally nontrivial cases. This contributes to an understanding of how energy may be stored or accumulated in the form of bound states of Schr\\"odinger - type quantum systems that are devoid of any mass.
Low-lying charmed and charmed-strange baryon states
Energy Technology Data Exchange (ETDEWEB)
Chen, Bing [Anyang Normal University, Department of Physics, Anyang (China); Institute of Modern Physics of CAS and Lanzhou University, Research Center for Hadron and CSR Physics, Lanzhou (China); Wei, Ke-Wei [Anyang Normal University, Department of Physics, Anyang (China); Liu, Xiang [Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Institute of Modern Physics of CAS and Lanzhou University, Research Center for Hadron and CSR Physics, Lanzhou (China); Matsuki, Takayuki [Tokyo Kasei University, Tokyo (Japan); Nishina Center, RIKEN, Theoretical Research Division, Saitama (Japan)
2017-03-15
In this work, we systematically study the mass spectra and strong decays of 1P and 2S charmed and charmed-strange baryons in the framework of non-relativistic constituent quark models. With the light quark cluster-heavy quark picture, the masses are simply calculated by a potential model. The strong decays are studied by the Eichten-Hill-Quigg decay formula. Masses and decay properties of the well-established 1S and 1P states can be reproduced by our method. Σ{sub c}(2800){sup 0,+,++} can be assigned as a Σ{sub c2}(3/2{sup -}) or Σ{sub c2}(5/2{sup -}) state. We prefer to interpret the signal Σ{sub c}(2850){sup 0} as a 2S(1/2{sup +}) state although at present we cannot thoroughly exclude the possibility that this is the same state as Σ{sub c}(2800){sup 0}. Λ{sub c}(2765){sup +} or Σ{sub c}(2765){sup +} could be explained as the Λ{sub c}{sup +}(2S) state or Σ{sup +}{sub c1}(1/2{sup -}) state, respectively. We propose to measure the branching ratio of B(Σ{sub c}(2455)π)/B(Σ{sub c}(2520)π) in the future, which may disentangle the puzzle of this state. Our results support Ξ{sub c}(2980){sup 0,+} as the first radial excited state of Ξ{sub c}(2470){sup 0,+} with J{sup P} = 1/2{sup +}. The assignment of Ξ{sub c}(2930){sup 0} is analogous to Σ{sub c}(2800){sup 0,+,++}, i.e., a Ξ{sup '}{sub c2}(3/2{sup -}) or Ξ{sup '}{sub c2}(5/2{sup -}) state. In addition, we predict some typical ratios among partial decay widths, which are valuable for experimental search for these missing charmed and charmed-strange baryons. (orig.)
Low-lying ($K^{} = 0^{+}$) states of gadolinium isotopes
Indian Academy of Sciences (India)
Harun Reşit Yazar
2013-10-01
The sd-interacting boson approximation (sd-IBA) and the df-interacting boson approximation (df-IBA) can be related to each other and the states of the interacting boson approximation model can be identified with the fully symmetric states in the sdf interacting boson approximation model. A systematic study of the sdf-IBA model showed that the constructed Hamiltonian can successfully describe the strong octupole correlations in the deformed nuclei. We showed that the interacting boson approximation may account for many of these $K^{} = 0^{+}$ states. It was found that the calculated energy spectra of the gadolinium isotopes agree quite well with the experimental data. The observed (2) values were also calculated and compared with the experimental data.
Electron delocalization and aromaticity in low-lying excited states of archetypal organic compounds.
Feixas, Ferran; Vandenbussche, Jelle; Bultinck, Patrick; Matito, Eduard; Solà, Miquel
2011-12-14
Aromaticity is a property usually linked to the ground state of stable molecules. Although it is well-known that certain excited states are unquestionably aromatic, the aromaticity of excited states remains rather unexplored. To move one step forward in the comprehension of aromaticity in excited states, in this work we analyze the electron delocalization and aromaticity of a series of low-lying excited states of cyclobutadiene, benzene, and cyclooctatetraene with different multiplicities at the CASSCF level by means of electron delocalization measures. While our results are in agreement with Baird's rule for the aromaticity of the lowest-lying triplet excited state in annulenes having 4nπ-electrons, they do not support Soncini and Fowler's generalization of Baird's rule pointing out that the lowest-lying quintet state of benzene and septet state of cyclooctatetraene are not aromatic.
Isomerism of low-lying states in {sup 86}Y
Energy Technology Data Exchange (ETDEWEB)
Rusu, C. [Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest (Romania); University of Texas at Dallas, School of Natural Sciences and Mathematics, Richardson, TX (United States); Bucurescu, D.; Marginean, N.; Ionescu-Bujor, M.; Iordachescu, A.; Cata-Danil, G.; Cata-Danil, I.; Deleanu, D.; Filipescu, D.; Ghita, D.; Glodariu, T.; Ivascu, M.; Mihai, C.; Marginean, R.; Pascu, S.; Sava, T.; Stroe, L.; Suliman, G.; Zamfir, N.V. [Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest (Romania)
2010-04-15
Low-energy isomeric states of {sup 86}Y were populated in the reaction {sup 73}Ge + {sup 16}O at 57MeV and were investigated by means of delayed n {gamma} and {gamma} {gamma} coincidences. A half-life of 70(7)ns was measured for the 5{sup -} state at 208keV, yielding an exceptionally small B(M1) value of 2.0(7) x 10{sup -5} W.u. and a B(E2) value of 0.34({sup +24} {sub -13}) W.u. For the other three known isomeric states at 218, 243, and 302keV, the half-lives extracted from the present experimental data are in very good agreement with previous measurements. Given the newly observed isomeric character of the 5{sup -} 208keV state, the re-analysis of earlier experimental data on the 302keV isomer led to a new spin-parity assignment, 6{sup +}, for this state. In addition, this re-evaluation provided two g -factors, -0.083(3) and +0.63(2), for the 208 and 302keV states, respectively. The results are discussed in terms of spherical-shell model calculations performed with a truncated space of configurations built on the f{sub 5/2}, p{sub 3/2}, p{sub 1/2}, and g{sub 9/2} valence orbitals. Effective spin, orbital, and ''tensor'' g -factors were determined empirically for protons and neutrons in the considered configuration space. (orig.)
Theoretical characterization of low-lying electronic states of FCO
Francisco, Joseph S.; Goldstein, Avery N.; Robb, Michael A.; Williams, Ian H.
1992-03-01
The electronic and vibrational spectra of the fluoroformyl radical FCO are discussed in the light of ab initio (CASSCF(5 in 4)/6-31+G* and UMP2/6-311G*) calculated adiabatic and vertical transition energies, and vibrational frequencies, for the X 2A', A 2A″, B 2A', and C 2A″ states. Results for the formyl radical HCO are also presented for comparison.
Second Bound State of Biexcitons in Quantum Dots
Institute of Scientific and Technical Information of China (English)
XIE Wen-Eang
2003-01-01
The second bound state of the biexcitons in a quantum dot, with orbital angular momentum L = 1, is reported. By using the method of few-body physics, the binding energy spectra of the second bound state of a biexciton in a GaAs quantum dot with a parabolic confinement have been calculated as a function of the electron-to-hole mass ratio and the quantum dot size. The fact that the biexcitons have a second bound state may aid in the better understanding of their binding mechanism.
Mass spectrum bound state systems with relativistic corrections
Energy Technology Data Exchange (ETDEWEB)
Dineykhan, M; Zhaugasheva, S A [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna (Russian Federation); Toinbaeva, N Sh; Jakhanshir, A [al-Farabi Kazak National University, 480012 Almaty (Kazakhstan)
2009-07-28
Based on the investigation of the asymptotic behaviour of the polarization loop function for charged n scalar particles in an external gauge field, we determine the interaction Hamiltonian including relativistic corrections. The mass spectrum of the bound state is analytically derived. The mechanism for arising of the constituent mass of the relativistic bound-state forming particles is explained. The mass and the constituent mass of the two-, three- and n-body relativistic bound states are calculated taking into account relativistic corrections. The corrections arising due to the one- and two-loop electron polarization to the energy spectrum of muonic hydrogen with orbital and radial excitations are calculated.
Bound states of spinning black holes in five dimensions
Crichigno, P Marcos; Vandoren, Stefan
2016-01-01
We find and study supergravity BPS bound states of five-dimensional spinning black holes in asymptotically flat spacetime. These solutions follow from multi-string solutions in six-dimensional minimal supergravity and can be uplifted to F-theory or M-theory. We analyze the regularity conditions and work out the example of a bound state of two black holes in detail. The bound state is supported by fluxes through nontrivial topologies exterior to the horizons and KK momentum. Furthermore, we determine the entropy and compare with other macroscopic BPS solutions.
Global Correlations for Low-Lying Collective 2+ States
Qin, Z. Z.; Lei, Y.; Pittel, S.; Bijker, R.
2017-07-01
By using the triaxial rotor model and the anharmonic vibrator model with phonon mixing, we derive a global correlation between the quadrupole moments of the two lowest 2+ states in collective nuclei that had previously been observed in experimental data across the periodic table. We then derive other electromagnetic properties for these two models of nuclear structure and compare them globally with experimental data. We find that both models are able to robustly describe the experimental data across the region of nuclei for which the models are applicable, including a large number that they have in common. We then show that there seems to exists a robust orthogonal transformation between these two models for realistic nuclear systems, suggesting that these two seemingly diverse descriptions of quadrupole collective phenomena seem to act in a similar model space and may therefore have a common origin.
Entanglement bounds for squeezed non-symmetric thermal state
Jiang, L
2003-01-01
I study the three parameters bipartite quantum Gaussian state called squeezed asymmetric thermal state, calculate Gaussian entanglement of formation analytically and the up bound of relative entropy of entanglement, compare them with coherent information of the state. Based on the result obtained, it is anticipated that hashing inequality is not violated for squeezed non-symmetric thermal state.
Spectroscopy of high-lying states in actinide nuclei
Energy Technology Data Exchange (ETDEWEB)
Ahmad, I.; Back, B.B.; Betts, R.R. [and others
1995-08-01
In the course of studying positron-electron production during the collisions of uranium beams and tantalum targets, a careful measurement of the emitted gamma radiation was made using large Ge detectors. Many new high energy gamma rays were found, associated both with U-like and Ta-like fragments. To determine the origin of these gamma rays, a dedicated set of improved gamma-ray studies were carried out. The studies used four large (> 55%) Ge detectors mounted in the APEX chamber. States in {sup 238}U and {sup 232}Th were Coulomb excited using a {sup 208}Pb beam of 5.8 MeV/u. Heavy ions were detected in the large-area APEX multiwire proportional counters. The extensive beam monitoring of the APEX setup allowed precise normalization and accurate cross-section determinations. The Doppler shifts from upstream and downstream detectors permitted a precise confirmation of the incident beam energy to less than 0.05 MeV/A. A spectrum of gamma rays, corrected assuming emission from {sup 238}U.
Energies of low-lying excited states of linear polyenes.
Christensen, Ronald L; Galinato, Mary Grace I; Chu, Emily F; Howard, Jason N; Broene, Richard D; Frank, Harry A
2008-12-11
Room temperature absorption and emission spectra of the all-trans isomers of decatetraene, dodecapentaene, tetradecahexaene, and hexadecaheptaene have been obtained in a series of nonpolar solvents. The resolved vibronic features in the optical spectra of these model systems allow the accurate determination of S(0) (1(1)A(g)(-)) --> S(2) (1(1)B(u)(+)) and S(1) (2(1)A(g)(-)) --> S(0) (1(1)A(g)(-)) electronic origins as a function of solvent polarizability. These data can be extrapolated to predict the transition energies in the absence of solvent perturbations. The effects of the terminal methyl substituents on the transition energies also can be estimated. Franck-Condon maxima in the absorption and emission spectra were used to estimate differences between S(0) (1(1)A(g)(-)) --> S(1) (2(1)A(g)(-)) and S(0) (1(1)A(g)(-)) --> S(2) (1(1)B(u)(+)) electronic origins and "vertical" transition energies. Experimental estimates of the vertical transition energies of unsubstituted, all-trans polyenes in vacuum as a function of conjugation length are compared with long-standing multireference configuration interaction (MRCI) treatments and with more recent ab initio calculations of the energies of the 2(1)A(g)(-) (S(1)) and 1(1)B(u)(+) (S(2)) states.
Disjoint nonclassical hydrocarbons have very unstable lowest-lying singlet states: a PM3 study
Directory of Open Access Journals (Sweden)
Richard Francis Langler
2001-12-01
Full Text Available Earlier workers have suggested that disjoint hydrocarbons have nearly-degenerate lowest-lying singlet and triplet states while non-disjoint (or joint hydrocarbons should be ground-state triplets. PM3 results for an appropriate selection of alternant hydrocarbons are inconsistent with that generalization: disjoint, nonclassical, alternant hydrocarbons show the strongest predilection for triplet ground states.
Quasi-bound states in strained graphene
Bahamon, Dario; Qi, Zenan; Park, Harold; Pareira, Vitor; Campbell, David
In this work, we explore the possibility of manipulating electronic states in graphene nanostructures by mechanical means. Specifically, we use molecular dynamics and tight-binding models to access the electronic and transport properties of strained graphene nanobubbles and graphene kirigami. We establish that low energy electrons can be confined in the arms of the kirigami and within the nanobubbles; under different load conditions the coupling between confined states and continuous states is modified creating different conductance line-shapes.
Institute of Scientific and Technical Information of China (English)
冯东太; 丁世良; 王美山
2003-01-01
The highly excited vibrational states of asymmetric linear tetratomic molecules are studied in the framework of Lie algebra. By using symmetric group U1(4) U2(4) U3(4), we construct the Hamiltonian that includes not only Casimir operators but also Majorana operators M12,M13 and M23, which are useful for getting potential energy surface and force constants in Lie algebra method. By Lie algebra treatment, we obtain the eigenvalues of the Hamiltonian, and make the concrete calculation for molecule C2HF.
Coincidence spectroscopy of high-lying Rydberg states produced in strong laser fields
Larimian, Seyedreza; Erattupuzha, Sonia; Lemell, Christoph; Yoshida, Shuhei; Nagele, Stefan; Maurer, Raffael; Baltuška, Andrius; Burgdörfer, Joachim; Kitzler, Markus; Xie, Xinhua
2016-09-01
We demonstrate the detection of high-lying Rydberg states produced in strong laser fields with coincidence spectroscopy. Electron emission after the interaction of strong laser pulses with atoms and molecules is measured together with the parent ions in coincidence measurements. These electrons originate from high-lying Rydberg states with quantum numbers from n ˜20 up to n ≲120 formed by frustrated field ionization. Ionization rates are retrieved from the measured ionization signal of these Rydberg states. Simulations show that both tunneling ionization by a weak dc field and photoionization by blackbody radiation contribute to delayed electron emission on the nano- to microsecond scale. Furthermore, the dependence of the Rydberg-state production on the ellipticity of the driving laser field indicates that such high-lying Rydberg states are populated through electron recapture. The present experiment provides detailed quantitative information on Rydberg production in strong-field interaction.
On the bound states for the Aharonov-Casher systems
Silva, E O; Belich, H; Filgueiras, C
2012-01-01
The bound states for the Aharonov-Casher problem is considered. According to the Hagen's work on the exact equivalence between spin-1/2 Aharonov-Bohm and Aharonov-Casher effects, is known that the $\\boldsymbol{\
Bound states of two-dimensional relativistic harmonic oscillators
Institute of Scientific and Technical Information of China (English)
Qiang Wen-Chao
2004-01-01
We give the exact normalized bound state wavefunctions and energy expressions of the Klein-Gordon and Dirac equations with equal scalar and vector harmonic oscillator potentials in the two-dimensional space.
Higgs interchange and bound states of superheavy fermions
Indian Academy of Sciences (India)
M De Sanctis
2013-09-01
Hypothetical superheavy fourth-generation fermions with a very small coupling with the rest of the Standard Model can give rise to long enough lived bound states. The production and the detection of these bound states would be experimentally feasible at the LHC. Extending, in the present study, the analysis of other authors, a semirelativistic wave equation is solved using an accurate numerical method to determine the binding energies of these possible superheavy fermion-bound states. The interaction given by the Yukawa potential of the Higgs boson exchange is considered; the corresponding relativistic corrections are calculated by means of a model based on the covariance properties of the Hamiltonian. We study the effects given by the Coulomb force. Moreover, we calculate the contributions given by the Coulombic and confining terms of the strong interaction in the case of superheavy quark bound states. The results of the model are critically analysed.
Rotationally invariant bipartite states and bound entanglement
Augusiak, R; Augusiak, Remigiusz; Stasi\\'{n}ska, Julia
2007-01-01
We consider rotationally invariant states in $\\mathbb{C}^{N_{1}}\\ot \\mathbb{C}^{N_{2}}$ Hilbert space with even $N_{1}\\geq 4$ and arbitrary $N_{2}\\geq N_{1}$, and show that in such case there always exist states which are inseparable and remain positive after partial transposition, and thus the PPT criterion does not suffice to prove separability of such systems. We demonstrate it applying a map developed recently by Breuer [H.-P. Breuer, Phys. Rev. Lett {\\bf 97}, 080501 (2006)] to states that remain invariant after partial time reversal.
Multicomponent Group-Related Coherent States for Lie Group Chain G K
Institute of Scientific and Technical Information of China (English)
HE Hui-Yong; LI Guang-Hua; LI Jiang-Fan
2001-01-01
The multicomponent group-related coherent states for the Lie group chain G K are introduced. Their coupling coefficients are presented. The relations between these coupling coefficients and those (in the usual sense) of the irreducible representation bases labelled by G K are obtained. The generalized Racah's factorization lemma about the coupling coefficients of such coherent states is given. As an example, the multicomponent group-related coherent states for the Lie group chain Sp(4) D SO(3)1 S0(3)2 are found. The uncertainty relation and the squeezing property are discussed.``
Narrow deeply bound K- and p atomic states
Friedman, E.; Gal, A.
2000-01-01
Examples of recently predicted narrow `deeply bound' K- and p atomic states are shown. The saturation of widths for strong absorptive potentials due to the induced repulsion, and the resulting suppression of atomic wave functions within the nucleus, are demonstrated. Production reactions for K- atomic states using φ(1020) decay, and the (p,p) reaction for p atomic states, are discussed.
NOON states via a quantum walk of bound particles
Compagno, Enrico; Banchi, Leonardo; Gross, Christian; Bose, Sougato
2017-01-01
Tight-binding lattice models allow the creation of bound composite objects which, in the strong-interacting regime, are protected against dissociation. We show that a local impurity in the lattice potential can generate a coherent split of an incoming bound particle wave packet which consequently produces a NOON state between the endpoints. This is nontrivial because, when finite lattices are involved, edge-localization effects render challenging their use for nonclassical state generation and information transfer. We derive an effective model to describe the propagation of bound particles in a Bose-Hubbard chain. We introduce local impurities in the lattice potential to inhibit localization effects and to split the propagating bound particle, thus enabling the generation of distant NOON states. We analyze how minimal engineering transfer schemes improve the transfer fidelity and we quantify the robustness to typical decoherence effects in optical lattice implementations. Our scheme potentially has an impact on quantum-enhanced atomic interferometry in a lattice.
Effects of QCD bound states on dark matter relic abundance
Liew, Seng Pei; Luo, Feng
2017-02-01
We study scenarios where there exists an exotic massive particle charged under QCD in the early Universe. We calculate the formation and dissociation rates of bound states formed by pairs of these particles, and apply the results in dark matter (DM) coannihilation scenarios, including also the Sommerfeld effect. We find that on top of the Sommerfeld enhancement, bound-state effects can further significantly increase the largest possible DM masses which can give the observed DM relic abundance, by ˜ 30-100% with respect to values obtained by considering the Sommerfeld effect only, for the color triplet or octet exotic particles we consider. In particular, it indicates that the Bino DM mass in the right-handed stop-Bino coannihilation scenario in the Minimal Supersymmetric extension of the Standard Model (MSSM) can reach ˜ 2.5 TeV, even though the potential between the stop and antistop prior to forming a bound state is repulsive. We also apply the bound-state effects in the calculations of relic abundance of long-lived or metastable massive colored particles, and discuss the implications on the BBN constraints and the abundance of a super-weakly interacting DM. The corrections for the bound-state effect when the exotic massive colored particles also carry electric charges, and the collider bounds are also discussed.
EXCITATION OF LOW-LYING STATES IN ND-144 BY MEANS OF (E,E') SCATTERING
PERRINO, R; BLASI, N; DELEO, R; HARAKEH, MN; DEJAGER, CW; MICHELETTI, S; MIEREMET, J; PIGNANELLI, M; PONOMAREV, VY; SANDOR, RKJ; DEVRIES, H
1993-01-01
The low-lying states of Nd-144 have been investigated up to an excitation energy of 3.1 MeV by means of high-resolution inelastic electron scattering. Transition charge densities have been extracted for natural-parity states. The experimental data have been compared with the predictions of the quasi
Bound and continuum vibrational states of the bifluoride anion
Špirko, V.; Šindelka, M.; Shirsat, R. N.; Leszczynski, J.
2003-07-01
The energies of the bound vibrational states and energy density spectra of the continuum vibrational states of FHF - are calculated, 'exactly' and 'adiabatically', using a new ab initio (CCSD(T)) potential energy surface. Statistical properties of the bound states are probed in terms of the density of states and nearest neighbor level spacing distributions (NNSD). Importantly, the approximate 'adiabatic' densities coincide nearly quantitatively with their 'exact' counterparts. A quantitative fitting of the NNSDs is achieved with a new empirical modification of the Wigner distribution.
Floquet bound states around defects and adatoms in graphene
Lovey, D. A.; Usaj, Gonzalo; Foa Torres, L. E. F.; Balseiro, C. A.
2016-06-01
Recent studies have focused on laser-induced gaps in graphene which have been shown to have a topological origin, thereby hosting robust states at the sample edges. While the focus has remained mainly on these topological chiral edge states, the Floquet bound states around defects lack a detailed study. In this paper we present such a study covering large defects of different shape and also vacancy-like defects and adatoms at the dynamical gap at ℏ Ω /2 (ℏ Ω being the photon energy). Our results, based on analytical calculations as well as numerics for full tight-binding models, show that the bound states are chiral and appear in a number which grows with the defect size. Furthermore, while the bound states exist regardless of the type of the defect's edge termination (zigzag, armchair, mixed), the spectrum is strongly dependent on it. In the case of top adatoms, the bound state quasienergies depend on the adatoms energy. The appearance of such bound states might open the door to the presence of topological effects on the bulk transport properties of dirty graphene.
Bound States of a Ferromagnetic Wire in a Superconductor.
Sau, Jay D; Brydon, P M R
2015-09-18
We consider the problem of bound states in strongly anisotropic ferromagnetic impurities in a superconductor, motivated by recent experiments that claim to observe Majorana modes at the ends of ferromagnetic wires on a superconducting substrate [S. Nadj-Perge et al., Science 346, 602 (2014)]. Generalizing the successful theory of bound states of spherically symmetric impurities, we consider a wirelike potential using both analytical and numerical approaches. We find that away from the ends of the wire the bound states form bands with pronounced van Hove singularities, giving rise to subgap peaks in the local density of states. For sufficiently strong magnetization of the wire, we show that this process generically produces a sharp peak at zero energy in the local density of states near the ends of the wire. This zero-energy peak has qualitative similarities to the claimed signature of a Majorana mode observed in the aforementioned experiment.
Low-lying Photoexcited States of a One-Dimensional Ionic Extended Hubbard Model
Yokoi, Kota; Maeshima, Nobuya; Hino, Ken-ichi
2017-10-01
We investigate the properties of low-lying photoexcited states of a one-dimensional (1D) ionic extended Hubbard model at half-filling. Numerical analysis by using the full and Lanczos diagonalization methods shows that, in the ionic phase, there exist low-lying photoexcited states below the charge transfer gap. As a result of comparison with numerical data for the 1D antiferromagnetic (AF) Heisenberg model, it was found that, for a small alternating potential Δ, these low-lying photoexcited states are spin excitations, which is consistent with a previous analytical study [Katsura et al., Phys. Rev. Lett. 103, 177402 (2009)]. As Δ increases, the spectral intensity of the 1D ionic extended Hubbard model rapidly deviates from that of the 1D AF Heisenberg model and it is clarified that this deviation is due to the neutral-ionic domain wall, an elementary excitation near the neutral-ionic transition point.
DEFF Research Database (Denmark)
Sadrieva, Z. F.; Sinev, I. S.; Samusev, A. K.;
2016-01-01
In this work, we implement CMOS-compatible one-dimensional photonic structure based on silicon-on-insulator wafer supporting optical bound states in the continuum at telecommunication wavelengths — localized optical state with energy lying above the light line of the surrounding space. Such high-......-Q states are very promising for many potential applications ranging from on-chip photonics and optical communications to biological sensing and photovoltaics....
Boson bound states in the -Fermi–Pasta–Ulam model
Indian Academy of Sciences (India)
Xin-Guang Hu; Ju Xiang; Zheng Jiao; Yang Liu; Guo-Qiu Xie; Ke Hu
2013-11-01
The bound states of four bosons in the quantum -Fermi–Pasta–Ulam model are investigated and some interesting results are presented using the number conserving approximation combined with the number state method. We find that the relative magnitude of anharmonic coefficient has a significant effect on forming localized energy in the model, and the wave number plays an important role in forming different bound states. The signature of the quantum breather is also set up by the square of the amplitudes of the corresponding eigenvectors in real space.
Two-body bound states in quantum electrodynamics. [Rate
Energy Technology Data Exchange (ETDEWEB)
Lepage, G.P.
1978-07-01
Novel formulations of the two-body bound state problem in quantum field theory are examined. While equal in rigor, these have several calculational advantages over the traditional Bethe-Salpeter formalism. In particular there exist exact solutions of the bound state equations for a Coulomb-like interaction in quantum electrodynamics. The corrections to such zeroth-order solutions can be systematically computed in a simple perturbation theory. These methods are illustrated by computing corrections to the orthopositronium decay rate and to the ground state splittings in positronium and muonium.
Bound states in open coupled asymmetrical waveguides and quantum wires
Amore, Paolo; Terrero-Escalante, Cesar A
2011-01-01
The behavior of bound states in asymmetric cross, T and L shaped configurations is considered. Because of the symmetries of the wavefunctions, the analysis can be reduced to the case of an electron localized at the intersection of two orthogonal crossed wires of different width. Numerical calculations show that the fundamental mode of this system remains bound for the widths that we have been able to study directly; moreover, the extrapolation of the results obtained for finite widths suggests that this state remains bound even when the width of one arm becomes infinitesimal. We provide a qualitative argument which explains this behavior and that can be generalized to the lowest energy states in each symmetry class. In the case of odd-odd states of the cross we find that the lowest mode is bounded when the width of the two arms is the same and stays bound up to a critical value of the ratio between the widths; in the case of the even-odd states we find that the lowest mode is unbound up to a critical value of...
Two-body bound state problem and nonsingular scattering equations
Energy Technology Data Exchange (ETDEWEB)
Bartnik, E.A.; Haberzettl, H.; Sandhas, W.
1986-11-01
We present a new momentum space approach to the two-body problem in partial waves. In contrast to the usual momentum space approaches, we treat the bound state case with the help of an inhomogeneous integral equation which possesses solutions for all (negative) energies. The bound state energies and corresponding wave functions are identified by an additional condition. This procedure straightforwardly leads to a nonsingular formulation of the scattering problem in terms of essentially the same equation and thus unifies the descriptions of both energy regimes. We show that the properties of our momentum-space approach can be understood in terms of the so-called regular solution of the Schroedinger equation in position space. The unified description of the bound state and scattering energy regimes in terms of one single, real, and manifestly nonsingular equation allows us to construct an exact representation of the two-body off-shell T matrix in which all the bound state pole and scattering cut information is contained in one single separable term, the remainder being real, nonsingular, and vanishing half on-shell. Such a representation may be of considerable advantage as input in three-body Faddeev-type integral equations. We demonstrate the applicability of our method by calculating bound state and scattering data for the two-nucleon system with the s-wave Malfliet--Tjon III potential.
Photodisintegration of a Bound State on the Torus
Meyer, Harvey B
2012-01-01
In this article the cross-section for the photodisintegration of a bound state is expressed, order by order in the multipole expansion, in terms of matrix elements between states living on the three-dimensional torus. The motivation is to make the process amenable to Monte-Carlo simulations. The case of the deuteron is discussed.
Search for bound-state electron+positron pair decay
Bosch, F.; Hagmann, S.; Hillenbrand, P.-M.; Lane, G. J.; Litvinov, Yu. A.; Reed, M. W.; Sanjari, M. S.; Stöhlker, Th.; Torilov, S. Yu.; Tu, X. L.; Walke, P. M.
2016-09-01
The heavy ion storage rings coupled to in-flight radioactive-ion beam facilities, namely the ability to produce and store for extended periods of time radioactive nuclides in high atomic charge states, for the searchof yet unobserved decay mode - bound-state electron-positron pair decay.
Bound Electron States in Skew-symmetric Quantum Wire Intersections
2014-01-01
dots is that they lie far beneath the surface of the surround- ing material whose associated states are potentially meddlesome. Colloidal chemistry ... textbooks have posed problems dealing with these states, but the approaches used in these problems involved variational methods or limiting cases, which are...of the Introductory Quantum Mechanics textbook by D.J.Griffith (Pearson, 2005). My trial function that has been developed in this the- sis, has an
The variational-relaxation algorithm for finding quantum bound states
Schroeder, Daniel V.
2017-09-01
I describe a simple algorithm for numerically finding the ground state and low-lying excited states of a quantum system. The algorithm is an adaptation of the relaxation method for solving Poisson's equation, and is fundamentally based on the variational principle. It is especially useful for two-dimensional systems with nonseparable potentials, for which simpler techniques are inapplicable yet the computation time is minimal.
Relativistic bound state approach to fundamental forces including gravitation
Directory of Open Access Journals (Sweden)
Morsch H.P.
2012-06-01
Full Text Available To describe the structure of particle bound states of nature, a relativistic bound state formalism is presented, which requires a Lagrangian including scalar coupling of two boson fields. The underlying mechanisms are quite complex and require an interplay of overlapping boson fields and fermion-antifermion production. This gives rise to two potentials, a boson-exchange potential and one identified with the long sought confinement potential in hadrons. With minimal requirements, two elementary massless fermions (quantons - with and without charge - and one gauge boson, hadrons and leptons but also atoms and gravitational systems are described by bound states with electric and magnetic coupling between the charges and spins of quantons. No need is found for colour, Higgs-coupling and supersymmetry.
Bound state techniques to solve the multiparticle scattering problem
Carbonell, J; Fonseca, A C; Lazauskas, R
2013-01-01
Solution of the scattering problem turns to be very difficult task both from the formal as well as from the computational point of view. If the last two decades have witnessed decisive progress in ab initio bound state calculations, rigorous solution of the scattering problem remains limited to A$\\leq$4 case. Therefore there is a rising interest to apply bound-state-like methods to handle non-relativistic scattering problems. In this article the latest theoretical developments in this field are reviewed. Five fully rigorous methods will be discussed, which address the problem of nuclear collisions in full extent (including the break-up problem) at the same time avoiding treatment of the complicate boundary conditions or integral kernel singularities. These new developments allows to use modern bound-state techniques to advance significantly rigorous solution of the scattering problem.
RDDS lifetime measurements of low-lying superdeformed states in {sup 194}Hg
Energy Technology Data Exchange (ETDEWEB)
Kuehn, R.; Dewald, A.; Kruecken, R. [Universitaet Koeln (Germany)] [and others
1996-12-31
The lifetimes of three low-lying states in the superdeformed (SD) yrast band of {sup 194}Hg were measured by the recoil-distance Doppler-shift method. The deduced transition quadrupole moments, Q{sub t}, equal those extracted from a DSAM measurement for the high-lying states of the band corroborate the assumption that the decay out of SD bands does not strongly affect the structure of the corresponding states. By a simple mixing-model the decay can be described assuming a very small admixture of normal-deformed (ND) states to the decaying SD states. The deduced ND mixing amplitudes for the yrast SD bands in {sup 192,194}Hg and {sup 194}Pb are presented along with average transition quadrupole moments for the lower parts of the excited SD bands.
Iterative solutions for low lying excited states of a class of Schr(o)dinger equation
Institute of Scientific and Technical Information of China (English)
R.Friedberga; T.D.Lee; Zhao Wei-Qin
2006-01-01
The convergent iterative procedure for solving the groundstate Schr(o)dinger equation is extended to derive the excitation energy and the wavefunction of the low-lying excited states. The method is applied to the one-dimensional quartic potential problem. The results show that the iterative solution converges rapidly when the coupling g is not too small.
Iterative Solutions for Low Lying Excited States of a Class of Schroedinger Equation
Friedberg, R; Zhao, W Q
2006-01-01
The convergent iterative procedure for solving the groundstate Schroedinger equation is extended to derive the excitation energy and the wave function of the low-lying excited states. The method is applied to the one-dimensional quartic potential problem. The results show that the iterative solution converges rapidly when the coupling $g$ is not too small.
Coherent states, quantum gravity, and the Born- Oppenheimer approximation. II. Compact Lie groups
Stottmeister, Alexander; Thiemann, Thomas
2016-07-01
In this article, the second of three, we discuss and develop the basis of a Weyl quantisation for compact Lie groups aiming at loop quantum gravity-type models. This Weyl quantisation may serve as the main mathematical tool to implement the program of space adiabatic perturbation theory in such models. As we already argued in our first article, space adiabatic perturbation theory offers an ideal framework to overcome the obstacles that hinder the direct implementation of the conventional Born-Oppenheimer approach in the canonical formulation of loop quantum gravity. Additionally, we conjecture the existence of a new form of the Segal-Bargmann-Hall "coherent state" transform for compact Lie groups G, which we prove for G = U(1)n and support by numerical evidence for G = SU(2). The reason for conjoining this conjecture with the main topic of this article originates in the observation that the coherent state transform can be used as a basic building block of a coherent state quantisation (Berezin quantisation) for compact Lie groups G. But, as Weyl and Berezin quantisation for ℝ2d are intimately related by heat kernel evolution, it is natural to ask whether a similar connection exists for compact Lie groups as well. Moreover, since the formulation of space adiabatic perturbation theory requires a (deformation) quantisation as minimal input, we analyse the question to what extent the coherent state quantisation, defined by the Segal-Bargmann-Hall transform, can serve as basis of the former.
Short-range correlations in low-lying nuclear excited states
Mokhtar, S R; Lallena, A M; Mokhtar, Sherif R.; Co', Giampaolo; Lallena, Antonio M.
2000-01-01
The electromagnetic transitions to various low-lying excited states of 16O, 48Ca and 208Pb are calculated within a model which considers the short-range correlations. In general the effects of the correlations are small and do not explain the required quenching to describe the data.
THE ACQM THEORETICAL CALCULATION OF LOW—LYING EXCITED STATES FOR HeH
Institute of Scientific and Technical Information of China (English)
Q.Q.GOU; Z.Y.Huang; 等
1990-01-01
The Low-lying excited states of HeH have been calculated by arrangement channel quantum mechanics(ACQM),The calculated potential curves,equilibrium geometry,Rc.dissociation energy Dc.harmonic vibration frequency ω0 and quadratic force coustant F2 are comparable with Ci calculations.
Cluster Decay of the High-lying excited states in $^{14}$C
Tian, Z Y; Li, Z H; Lin, C J; Li, Q T; Ge, Y C; Lou, J L; Jiang, W; Li, J; Yang, Z H; Feng, J; Li, P J; Chen, J; Liu, Q; Zang, H L; Yang, B; Zhang, Y; Chen, Z Q; Liu, Y; Sun, X H; Ma, J; Jia, H M; Xu, X X; Yang, L; Ma, N R; Sun, L J
2016-01-01
A cluster-transfer experiment of $^9\\rm{Be}(^9\\rm{Be},^{14}\\rm{C}\\rightarrow\\alpha+^{10}\\rm{Be})\\alpha$ at an incident energy of 45 MeV was carried out in order to investigate the molecular structure in high-lying resonant states in $^{14}$C. This reaction is of extremely large $Q$-value, making it an excellent case to select the reaction mechanism and the final states in outgoing nuclei. The high-lying resonances in $^{14}$C are reconstructed for three sets of well discriminated final states in $^{10}$Be. The results confirm the previous decay measurements with clearly improved decay-channel selections and show also a new state at 23.5(1) MeV. The resonant states at 22.4(3) and 24.0(3) MeV decay primarily into the typical molecular states at about 6 MeV in $^{10}$Be, indicating a well developed cluster structure in these high-lying states in $^{14}$C. Further measurements of more states of this kind are suggested.
Cluster decay of the high-lying excited states in 14C
Tian, Z. Y.; Ye, Y. L.; Li, Z. H.; Lin, C. J.; Li, Q. T.; Ge, Y. C.; Lou, J. L.; Jiang, W.; Li, J.; Yang, Z. H.; Feng, J.; Li, P. J.; Chen, J.; Liu, Q.; Zang, H. L.; Yang, B.; Zhang, Y.; Chen, Z. Q.; Liu, Y.; Sun, X. H.; Ma, J.; Jia, H. M.; Xu, X. X.; Yang, L.; Ma, N. R.; Sun, L. J.
2016-11-01
A cluster-transfer experiment of 9Be(9Be,14C → α+10Be)α at an incident energy of 45 MeV was carried out in order to investigate the molecular structure in high-lying resonant states in 14C. This reaction is of extremely large Q-value, making it an excellent case to select the reaction mechanism and the final states in outgoing nuclei. The high-lying resonances in 14C are reconstructed for three sets of well discriminated final states in 10Be. The results confirm the previous decay measurements with clearly improved decay-channel selections and also show a new state at 23.5(1) MeV. The resonant states at 22.4(3) and 24.0(3) MeV decay primarily into the typical molecular states at about 6 MeV in 10Be, indicating a well developed cluster structure in these high-lying states in 14C. Further measurements of more states of this kind are suggested. Supported by the 973 Program of China (2013 CB834402) and National Natural Science Foundation of China (11275011, 11535004)
A theoretical study of the low-lying states of Ti2 and Zr2
Bauschlicher, Charles W., Jr.; Partridge, Harry; Langhoff, Stephen R.; Rosi, Marzio
1991-01-01
The low-lying states of Ti2 and the valence isoelectronic Zr2 are examined theoretically by means of a multireference configuration-interaction (MRCI) method. MRCI calculations demonstrate that two of the Zr2 states are very low-lying and that the resulting vertical excitation is consistent with the optical spectrum of Zr2. The ground state is predicted for Ti2 on the basis of valence correlation with the MRCI method and the average coupled-pair functional technique. Calculations of the inner-shell correlation effects are estimated and found to lower the 3Delta g state to a ground state, and another to a very low-lying state. The ground state of Ti2 is assigned to 3Delta g since it is lower than the other state at all levels of correlation and is derived from the same atomic asymptote. This conclusion is supported by the lack of an electron-spin resonance signal but contradicts the absence of subcomponents on the Raman spectral lines.
Bounding the persistency of the nonlocality of W states
Diviánszky, Péter; Trencsényi, Réka; Bene, Erika; Vértesi, Tamás
2016-04-01
The nonlocal properties of the W states are investigated under particle loss. By removing all but two particles from an N -qubit W state, the resulting two-qubit state is still entangled. Hence, the W state has high persistency of entanglement. We ask an analogous question regarding the persistency of nonlocality [see N. Brunner and T. Vértesi, Phys. Rev. A 86, 042113 (2012), 10.1103/PhysRevA.86.042113]. Namely, we inquire what is the minimal number of particles that must be removed from the W state so that the resulting state becomes local. We bound this value in function of N qubits by considering Bell nonlocality tests with two alternative settings per site. In particular, we find that this value is between 2 N /5 and N /2 for large N . We also develop a framework to establish bounds for more than two settings per site.
Force-producing ADP state of myosin bound to actin.
Wulf, Sarah F; Ropars, Virginie; Fujita-Becker, Setsuko; Oster, Marco; Hofhaus, Goetz; Trabuco, Leonardo G; Pylypenko, Olena; Sweeney, H Lee; Houdusse, Anne M; Schröder, Rasmus R
2016-03-29
Molecular motors produce force when they interact with their cellular tracks. For myosin motors, the primary force-generating state has MgADP tightly bound, whereas myosin is strongly bound to actin. We have generated an 8-Å cryoEM reconstruction of this state for myosin V and used molecular dynamics flexed fitting for model building. We compare this state to the subsequent state on actin (Rigor). The ADP-bound structure reveals that the actin-binding cleft is closed, even though MgADP is tightly bound. This state is accomplished by a previously unseen conformation of the β-sheet underlying the nucleotide pocket. The transition from the force-generating ADP state to Rigor requires a 9.5° rotation of the myosin lever arm, coupled to a β-sheet rearrangement. Thus, the structure reveals the detailed rearrangements underlying myosin force generation as well as the basis of strain-dependent ADP release that is essential for processive myosins, such as myosin V.
Flow Equations for N Point Functions and Bound States
Ellwanger, Ulrich
1994-01-01
We discuss the exact renormalization group or flow equation for the effective action and its decomposition into one particle irreducible N point functions. With the help of a truncated flow equation for the four point function we study the bound state problem for scalar fields. A combination of analytic and numerical methods is proposed, which is applied to the Wick-Cutkosky model and a QCD-motivated interaction. We present results for the bound state masses and the Bethe-Salpeter wave function. (Figs. 1-4 attached as separate uuencoded post-script files.)
Parity lifetime of bound states in a proximitized semiconductor nanowire
DEFF Research Database (Denmark)
Higginbotham, Andrew Patrick; Albrecht, Sven Marian; Kirsanskas, Gediminas
2015-01-01
superconductors but remain relatively unexplored in semiconductor-superconductor structures, which are now being intensely pursued in the context of topological superconductivity. To this end, we introduce a new physical system comprised of a gate-confined semiconductor nanowire with an epitaxially grown...... superconductor layer, yielding an isolated, proximitized nanowire segment. We identify Andreev-like bound states in the semiconductor via bias spectroscopy, determine the characteristic temperatures and magnetic fields for quasiparticle excitations, and extract a parity lifetime (poisoning time) of the bound...... state in the semiconductor exceeding 10 ms....
First direct proof of internal conversion between bound states
Carreyre, T.; Harston, M. R.; Aiche, M.; Bourgine, F.; Chemin, J. F.; Claverie, G.; Goudour, J. P.; Scheurer, J. N.; Attallah, F.; Bogaert, G.; Kiener, J.; Lefebvre, A.; Durell, J.; Grandin, J. P.; Meyerhof, W. E.; Phillips, W.
2000-08-01
We present direct evidence for the process of internal conversion between bound atomic states (BIC) when the binding energy of the converted electron becomes larger than the nuclear transition energy. This process has been proposed as an explanation of the measured, unexpectedly short lifetime of the first excited state of 125Te with charge state larger than 44+. We have detected the Kα x rays emitted in flight which follow the filling of the K-shell vacancy created by the bound internal conversion process, together with γ rays from Te ions in charge states ranging between 44+ and 48+. For Te45+ and Te46+, the comparison of the x-ray to γ-ray ratios with the theoretical calculations of the internal conversion coefficients including decay to bound atomic states, assuming Te ions in their ground electronic state, show poor agreement. The agreement becomes good if account is taken of BIC decay of excited initial states with different occupancies of the 2p1/2 and 2p3/2 subshells. In this situation, the half-life becomes sensitive to the precise initial state and simple specification of the charge state alone is no longer appropriate.
Helical bound states in the continuum of the edge states in two dimensional topological insulators
Energy Technology Data Exchange (ETDEWEB)
Sablikov, Vladimir A., E-mail: sablikov@gmail.com; Sukhanov, Aleksei A.
2015-09-04
We study bound states embedded into the continuum of edge states in two-dimensional topological insulators. These states emerge in the presence of a short-range potential of a structural defect coupled to the boundary. In this case the edge states flow around the defect and have two resonances in the local density of states. The bound state in continuum (BIC) arises due to an interference of the resonances when they are close to the degeneracy. We find the condition under which the BIC appears, study the spacial distribution of the electron density, and show that the BIC has a helical structure with an electron current circulating around the defect. - Highlights: • We find bound states in the continuum of edge states in 2D topological insulators. • The bound states are induced by an impurity potential and topological order. • The bound state in the continuum has a helical structure of spin and current density.
Directional detection of dark matter in universal bound states
Laha, Ranjan
2015-01-01
It has been suggested that several small-scale structure anomalies in $\\Lambda$CDM cosmology can be solved by strong self-interaction between dark matter particles. It was shown by Braaten and Hammer that the presence of a near threshold S-wave resonance can make the scattering cross section at nonrelativistic speeds come close to saturating the unitarity bound. This can result in the formation of a stable bound state of two asymmetric dark matter particles (which we call darkonium). Laha and Braaten studied the nuclear recoil energy spectrum in dark matter direct detection experiments due to this incident bound state. Here we study the angular recoil spectrum, and show that it is uniquely determined up to normalization by the S-wave scattering length. Observing this angular recoil spectrum in a dark matter directional detection experiment will uniquely determine many of the low-energy properties of dark matter independent of the underlying dark matter microphysics.
ɛ-bounded state estimation for time-delay systems with bounded disturbances
Nam, P. T.; Pathirana, P. N.; Trinh, H.
2014-09-01
A new problem on ε-bounded functional state estimation for time-delay systems with unknown bounded disturbances is studied in this paper. In the presence of unknown bounded disturbances, the common assumption regarding the observer's matching condition is no longer required. In this regard, instead of achieving asymptotic convergence for the observer error, the error is now required to converge exponentially within a ball with a small radius ε > 0. This means that the estimate converges exponentially within an ε-bound of the true value. A general observer that utilises multiple-delayed output and input information is proposed. Sufficient conditions for the existence of the proposed observer are first given. We then employ an extended Lyapunov-Krasovskii functional which combines the delay-decomposition technique with a triple-integral term to study the ε-convergence problem of the observer error system. Moreover, the obtained results are shown to be more effective than the existing results for the cases with no disturbances and/or no time delay. Three numerical examples are given to illustrate the obtained results.
The S-matrix of string bound states
Energy Technology Data Exchange (ETDEWEB)
Arutyunov, Gleb [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands)], E-mail: g.arutyunov@phys.uu.nl; Frolov, Sergey [School of Mathematics, Trinity College, Dublin 2 (Ireland)], E-mail: frolovs@maths.tcd.ie
2008-11-21
We find the S-matrix which describes the scattering of two-particle bound states of the light-cone string sigma model on AdS{sub 5}xS{sup 5}. We realize the M-particle bound state representation of the centrally extended su(2|2) algebra on the space of homogeneous (super)symmetric polynomials of degree M depending on two bosonic and two fermionic variables. The scattering matrix S{sup MN} of M- and N-particle bound states is a differential operator of degree M+N acting on the product of the corresponding polynomials. We require this operator to obey the invariance condition and the Yang-Baxter equation, and we determine it for the two cases M=1,N=2 and M=N=2. We show that the S-matrices found satisfy generalized physical unitarity, CPT invariance, parity transformation rule and crossing symmetry. Although the dressing factor as a function of four parameters x{sub 1}{sup +},x{sub 1}{sup -},x{sub 2}{sup +},x{sub 2}{sup -} is universal for scattering of any bound states, it obeys a crossing symmetry equation which depends on M and N.
Calculation of size for bound-state constituents
Glazek, Stanislaw D
2014-01-01
Elements are given of a calculation that identifies the size of a proton in the Schroedinger equation for lepton-proton bound states, using the renormalization group procedure for effective particles (RGPEP) in quantum field theory, executed only up to the second order of expansion in powers of the coupling constant. Already in this crude approximation, the extraction of size of a proton from bound-state observables is found to depend on the lepton mass, so that the smaller the lepton mass the larger the proton size extracted from the same observable bound-state energy splitting. In comparison of Hydrogen and muon-proton bound-state dynamics, the crude calculation suggests that the difference between extracted proton sizes in these two cases can be a few percent. Such values would match the order of magnitude of currently discussed proton-size differences in leptonic atoms. Calculations using the RGPEP of higher order than second are required for a precise interpretation of the energy splittings in terms of t...
Towards flavored bound states beyond rainbows and ladders
El-Bennich, B; Paracha, M A; de Melo, J P B C
2013-01-01
We give a snapshot of recent progress in solving the Dyson-Schwinger equation with a beyond rainbow-ladder ansatz for the dressed quark-gluon vertex which includes ghost contributions. We discuss the motivations for this approach with regard to heavy-flavored bound states and form factors and briefly describe future steps to be taken.
In-medium K̄ interactions and bound states
Directory of Open Access Journals (Sweden)
Gal Avraham
2014-01-01
Full Text Available Correct treatment of subthreshold K̄ N dynamics is mandatory in K− -atom and K̄ -nuclear bound-state calculations, as demonstrated by using in-medium chirally-based models of K̄ N interactions. Recent studies of kaonic atom data reveal appreciable multi-nucleon contributions. K̄ -nuclear widths larger than 50 MeV are anticipated.
A Lorentz covariant approach to the bound state problem
Micu, L
2000-01-01
The relativistic equivalent of the Schr\\"odinger equation for a two particle bound state having the total angular momentum $S$ is written in the form of a Lorentz covariant set of equations (p_1^mu+p_2^mu+Omega^mu)Psi(p_1,p_2;P) chi_S(\\vec{p}_1,\\vec{p}_2)=P^mu Psi(p_1,p_2;P) chi_S(\\vec{p}_1,\\vec{p}_2) where the operators Omega^mu are the components of a 4-vector quasipotential. The solution of this set is a stationary function representing the distribution of spins and internal momenta in a reference frame where the momentum of the bound system is P^\\mu. The contribution of the operators Omega^mu to the bound state momentum is assumed to be the 4-momentum of a vacuum-like effective field entering the bound system as an independent component. It is shown that a state made of free quarks and of the effective field has definite mass and can be normalized like a single particle state. The generalization to the case of three or more particles is immediate.
Towards flavored bound states beyond rainbows and ladders
Energy Technology Data Exchange (ETDEWEB)
El-Bennich, B.; Rojas, E.; Melo, J. P. B. C. de [Laboratório de Física Teórica e Computacional, Universidade Cruzeiro do Sul, São Paulo 01506-000 SP (Brazil); Paracha, M. A. [Laboratorio de Fisica Teorica e Computacional, Universidade Cruzeiro do Sul, Sao Paulo 01506-000 SP, Brazil and Centre for Advanced Mathematics and Physics, National University of Science and Technology, Islamabad (Pakistan)
2014-11-11
We give a snapshot of recent progress in solving the Dyson-Schwinger equation with a beyond rainbow-ladder ansatz for the dressed quark-gluon vertex which includes ghost contributions. We discuss the motivations for this approach with regard to heavy-flavored bound states and form factors and briefly describe future steps to be taken.
The S-matrix of String Bound States
Arutyunov, Gleb
2008-01-01
We find the S-matrix which describes the scattering of two-particle bound states of the light-cone string sigma model on AdS5xS5. We realize the M-particle bound state representation of the centrally extended su(2|2) algebra on the space of homogeneous (super)symmetric polynomials of degree M depending on two bosonic and two fermionic variables. The scattering matrix S^{MN} of M- and N-particle bound states is a differential operator of degree M+N acting on the product of the corresponding polynomials. We require this operator to obey the invariance condition and the Yang-Baxter equation, and we determine it for the two cases M=1,N=2 and M=N=2. We show that the S-matrices found satisfy generalized physical unitarity, CPT invariance, parity transformation rule and crossing symmetry. Although the dressing factor as a function of four parameters x_1^+,x_1^-,x_2^+,x_2^- is universal for scattering of any bound states, it obeys a crossing symmetry equation which depends on M and N.
The local characteristics of the bound states of muonic molecules
Energy Technology Data Exchange (ETDEWEB)
Abramov, D.I. [Sankt Peterburgskij Univ., St. Petersburg (Russian Federation); Bogdanova, L.N. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Gusev, V.V. [Institut Fiziki Vysokikh Ehnergij, Protvino (Russian Federation); Ponomarev, L.I. [Rossijskij Nauchnyj Tsentr ``Kurchatovskij Inst.``, Moscow (Russian Federation)
1996-10-01
The sticking probabilities {omega}{sup Jv}, G- and {gamma}-factors for all bound states of mesic molecules HH{mu}, HD{mu}, HT{mu}, DD{mu}, DT{mu}, and TT{mu} with J = 0 and v = 0, 1 have been calculated in the adiabatic hyperspherical approach (AHSA). (orig.). 6 refs.
Classification of lying states for the humanoid robot SJTU-HR1
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
The humanoid robot SJTU-HR1’s concept is introduced and its characteristics tree is given.The basic states for SJTU-HR1 are proposed,including lying,sitting,standing and handstanding,abstracted from the daily exercises of human beings.The GF(generalized function) set theory is exploited to achieve the kinematic characteristics of the interested EEs(end-effectors) of SJTU-HR1 for the lying states.Finally,the results show that the large amounts of states can be described using the abbreviations in a systematic manner.Although we have focused on the application of the GF set theory to humanoid robots,particularly the SJTU-HR1,this methodology can also be applied to quadruped robots and hexapedal robots,especially when the desired tasks are complex.
Classification of lying states for the humanoid robot SJTU-HR1
Institute of Scientific and Technical Information of China (English)
YANG JiaLun; GAO Feng; JIN ZhenLin; SHI LiFeng
2009-01-01
The humanoid robot SJTU-HRI's concept is introduced and its characteristics tree is given. The basic states for SJTU-HR1 are proposed, including lying, sitting, standing and handstsnding, abstracted from the daily exercises of human beings. The GF (generalized function) set theory is exploited to achieve the kinematic characteristics of the interested EEs (end-effectors) of SJTU-HR1 for the lying states.Finally, the results show that the large amounts of states can be described using the abbreviations in a systematic manner. Although we have focused on the application of the GF set theory to humanoid robots, particularly the SJTU-HR1, this methodology can also be applied to quadruped robots and hexapedal robots, especially when the desired tasks are complex.
Computed potential surfaces for six low-lying states of Ni3
Walch, Stephen P.
1987-01-01
Selected portions of the potential surfaces for six low lying states of Ni3 are the subject of the present SCF/CCI calculations using the effective core potentials developed by Hay and Wadt (1985); the four states are studied for near-equilateral triangle geometries are within 0.04 eV of each other. Two states are studied for linear geometries, of which the first is 0.16 eV higher than the corresponding near-equilateral triangle state and the second is estimated to be nearly degenerate with the near-equilateral triangle structures.
A model of low-lying states in strongly interacting electroweak symmetry-breaking sector
Han, T; Hung, P Q; Han, Tao; Huang, Zheng; Hung, P Q
1994-01-01
We present a tumbling scenario for the generation of low-lying states in a strongly interacting electroweak sector. The dynamical calculation using the N/D method indicates that when the interactions among the Goldstone and Higgs bosons become sufficiently strong, an axial vector state A_1 [I^G(J^P)=1^-(1^+)] emerges. The coexistence of vector states V [1^+(1^-)] and \\omega_H [0^-(1^-)] is suggested by requiring the proper Regge behavior of the forward scattering. These states may lead to distinctive experimental signatures at the future colliders.
Nonradiative formation of the positron-helium triplet bound state
di Rienzi, Joseph; Drachman, Richard J.
2007-02-01
We have previously calculated the cross section for radiative formation of the interesting bound state consisting of a positron bound to helium, where the atomic electrons are in the triplet spin state. That process uses the metastable triplet helium system as target, and, as expected, it has a very small cross section. In this paper we examine a more probable process in which the state of interest is produced in an exchange rearrangement collision between a positronium atom and the singlet helium ground state: Ps+He(Se1)→PsHe+(Se3)+e- . The present calculation is done in the plane-wave Born approximation, using simple initial and final wave functions and compares post and prior forms.
Does a proton "bubble" structure exist in the low-lying states of 34Si?
Yao, J M; Li, Z P
2013-01-01
The possible existence of a "bubble" structure in the proton density of $^{34}$Si has recently attracted a lot of research interest. To examine the existence of the "bubble" structure in low-lying states, we establish a relativistic version of configuration mixing of both particle number and angular momentum projected quadrupole deformed mean-field states and apply this state-of-the-art beyond relativistic mean-field method to study the density distribution of the low-lying states in $^{34}$Si. An excellent agreement with the data of low-spin spectrum and electric multipole transition strengths is achieved without introducing any parameters. We find that the central depression in the proton density is quenched by dynamic quadrupole shape fluctuation, but not as significantly as what has been found in a beyond non-relativistic mean-field study. Our results suggest that the existence of proton "bubble" structure in the low-lying excited $0^+_2$ and $2^+_1$ states is very unlikely.
Does \\Sigma -\\Sigma -\\alpha Form a Quasi-Bound State?
Htun Oo, H; Kamada, H; Glöckle, W
2004-01-01
We have investigated the possible existence of a quasi-bound state for the \\Sigma -\\Sigma -\\alpha system in the framework of Faddeev calculations. We are particularly interested in the state of total iso-spin T=2, since for an inert \\alpha particle there is no strong conversion to \\Xi -N-\\alpha or \\Lambda -\\Lambda -\\alpha possible. A \\Sigma -\\alpha optical potential based on Nijmegen model D and original \\Sigma -\\Sigma interactions of the series of Nijmegen potentials NSC97 as well a simulated Gaussian type versions thereof are used. Our investigation of the \\Sigma -\\Sigma -\\alpha system leads to a quasi bound state where, depending on the potential parameters, the energy ranges between -1.4 and -2.4 MeV and the level width is about 0.2MeV.
Probing Andreev bound states in one-atom superconducting contacts
Energy Technology Data Exchange (ETDEWEB)
Pothier, Hugues; Janvier, Camille; Tosi, Leandro; Girit, Caglar; Goffman, Marcelo; Esteve, Daniel; Urbina, Cristian [Quantronics Group, SPEC, CEA-Saclay (France)
2015-07-01
Superconductors are characterized by a dissipationless current. Since the work of Josephson 50 years ago, it is known that a supercurrent can even flow through tunnel junctions between superconductors. This Josephson effect also occurs through any type of ''weak links'' between superconductors: non-superconducting materials, constrictions,.. A unified understanding of the Josephson effect has emerged from a mesoscopic description of weak links. It relies on the existence of doublets of localized states that have energies below the superconducting gap: the Andreev bound states. I will present experiments performed on the simplest conductor possible, a single-atom contact between superconductors, that illustrate these concepts. The most recent work demonstrates time-domain manipulation of quantum superpositions of Andreev bound states.
Transition from vibrational to rotational character in low-lying states of hypernuclei
Mei, H.; Hagino, K.; Yao, J. M.; Motoba, T.
2017-07-01
In order to clarify the nature of hypernuclear low-lying states, we carry out a comprehensive study of the structure of Λ 145-155Sm hypernuclei, which exhibit a transition from vibrational to rotational character as the neutron number increases. To this end, we employ a microscopic particle-core coupling scheme based on a covariant density functional theory. We find that the positive-parity ground-state band in the hypernuclei shares a similar structure to that of the corresponding core nucleus. That is, regardless of whether the core nucleus is spherical or deformed, each hypernuclear state is dominated by the single configuration of the Λ particle in the s1 /2 state (Λ s1 /2 ) coupled to one core state of the ground band. In contrast, the low-lying negative-parity states mainly consist of Λ p1 /2 and Λ p3 /2 configurations coupled to plural nuclear core states. We show that, while the mixing amplitude between these configurations is negligibly small in spherical and weakly deformed nuclei, it strongly increases as the core nucleus undergoes a transition to a well deformed shape, which is consistent with the Nilsson wave functions. We demonstrate that the structure of these negative-parity states with spin I can be well understood based on a naive L S coupling scheme, with total orbital angular momentum L =[I ⊗1 ] and spin angular momentum S =1 /2 .
Shell model description of low-lying states in Po and Rn isotopes
Higashiyama, Koji; Yoshinaga, Naotaka
2014-03-01
Nuclear structure of the Po and Rn isotopes is theoretically studied in terms of the spherical shell model with the monopole- and quadrupole-pairing plus quadrupole-quadrupole effective interaction. The experimental energy levels of low-lying states are well reproduced. The shell model results are examined in detail in a pair-truncated shell model. The analysis reveals the alignment of two protons in the 0h9/2 orbital at spin 8.
Shell model description of low-lying states in Po and Rn isotopes
Directory of Open Access Journals (Sweden)
Higashiyama Koji
2014-03-01
Full Text Available Nuclear structure of the Po and Rn isotopes is theoretically studied in terms of the spherical shell model with the monopole- and quadrupole-pairing plus quadrupole-quadrupole effective interaction. The experimental energy levels of low-lying states are well reproduced. The shell model results are examined in detail in a pair-truncated shell model. The analysis reveals the alignment of two protons in the 0h9/2 orbital at spin 8.
How quantum bound states bounce and the structure it reveals
Lee, Dean
2010-01-01
We investigate how quantum bound states bounce from a hard surface. Our analysis has applications to ab initio calculations of nuclear structure and elastic deformation, energy levels of excitons in semiconductor quantum dots and wells, and cold atomic few-body systems on optical lattices with sharp boundaries. We develop the general theory of elastic reflection for a composite body from a hard wall. On the numerical side we present universal results for two-body states and discuss ab initio calculations for general few-body systems. On the analytical side we derive a universal effective potential that gives the reflection scattering length for shallow two-body states.
Observation of Andreev bound states at spin-active interfaces
Energy Technology Data Exchange (ETDEWEB)
Beckmann, Detlef; Wolf, Michael Johannes [KIT, Institut fuer Nanotechnologie (Germany); Huebler, Florian [KIT, Institut fuer Nanotechnologie (Germany); KIT, Institut fuer Festkoerperphysik (Germany); Loehneysen, Hilbert von [KIT, Institut fuer Festkoerperphysik (Germany); KIT, Physikalisches Institut (Germany)
2013-07-01
We report on high-resolution differential conductance experiments on nanoscale superconductor/ferromagnet tunnel junctions with ultra-thin oxide tunnel barriers. We observe subgap conductance features which are symmetric with respect to bias, and shift according to the Zeeman energy with an applied magnetic field. These features can be explained by resonant transport via Andreev bound states induced by spin-active scattering at the interface. From the energy and the Zeeman shift of the bound states, both the magnitude and sign of the spin-dependent interfacial phase shifts between spin-up and spin-down electrons can be determined. These results contribute to the microscopic insight into the triplet proximity effect at spin-active interfaces.
Parity lifetime of bound states in a proximitized semiconductor nanowire
Higginbotham, A. P.; Albrecht, S. M.; Kiršanskas, G.; Chang, W.; Kuemmeth, F.; Krogstrup, P.; Jespersen, T. S.; Nygård, J.; Flensberg, K.; Marcus, C. M.
2015-12-01
Quasiparticle excitations can compromise the performance of superconducting devices, causing high-frequency dissipation, decoherence in Josephson qubits, and braiding errors in proposed Majorana-based topological quantum computers. Quasiparticle dynamics have been studied in detail in metallic superconductors but remain relatively unexplored in semiconductor-superconductor structures, which are now being intensely pursued in the context of topological superconductivity. To this end, we use a system comprising a gate-confined semiconductor nanowire with an epitaxially grown superconductor layer, yielding an isolated, proximitized nanowire segment. We identify bound states in the semiconductor by means of bias spectroscopy, determine the characteristic temperatures and magnetic fields for quasiparticle excitations, and extract a parity lifetime (poisoning time) of the bound state in the semiconductor exceeding 10 ms.
Radial sensitivity of kaonic atoms and strongly bound K¯ states
Barnea, N.; Friedman, E.
2007-02-01
The strength of the low-energy K--nucleus real potential has recently received renewed attention in view of experimental evidence for the possible existence of strongly bound K- states. Previous fits to kaonic atom data led to either “shallow” or “deep” potentials, where only the former are in agreement with chiral approaches but only the latter can produce strongly bound states. Here we explore the uncertainties of the K--nucleus optical potentials, obtained from fits to kaonic atom data, using the functional derivatives of the best-fit χ2 values with respect to the potential. We find that only the deep type of potential provides information that is applicable to the K- interaction in the nuclear interior.
Understanding the nucleon as a Borromean bound-state
Directory of Open Access Journals (Sweden)
Jorge Segovia
2015-11-01
Full Text Available Analyses of the three valence-quark bound-state problem in relativistic quantum field theory predict that the nucleon may be understood primarily as a Borromean bound-state, in which binding arises mainly from two separate effects. One originates in non-Abelian facets of QCD that are expressed in the strong running coupling and generate confined but strongly-correlated colour-antitriplet diquark clusters in both the scalar–isoscalar and pseudovector–isotriplet channels. That attraction is magnified by quark exchange associated with diquark breakup and reformation. Diquark clustering is driven by the same mechanism which dynamically breaks chiral symmetry in the Standard Model. It has numerous observable consequences, the complete elucidation of which requires a framework that also simultaneously expresses the running of the coupling and masses in the strong interaction. Planned experiments are capable of validating this picture.
Three-body structure of low-lying {sup 18}Ne states
Energy Technology Data Exchange (ETDEWEB)
Lay, J.A. [Universidad de Sevilla, Departamento de Fisica Atomica, Molecular y Nuclear, Sevilla (Spain); Fedorov, D.V.; Jensen, A.S. [Aarhus University, Department of Physics and Astronomy, Aarhus C (Denmark); Garrido, E.; Romero-Redondo, C. [CSIC, Instituto de Estructura de la Materia, Madrid (Spain)
2010-05-15
We investigate to what extent {sup 18}Ne can be descibed as a three-body system made of an inert {sup 16}O core and two protons. We compare to experimental data and occasionally to shell model results. We obtain three-body wave functions with the hyperspherical adiabatic expansion method. We study the spectrum of {sup 18}Ne, the structure of the different states and the predominant transition strengths. Two 0{sup +}, two 2{sup +}, and one 4{sup +} bound states are found where they are all known experimentally. Also one 3{sup +} close to threshold is found and several negative-parity states, 1{sup -}, 3{sup -}, 0{sup -}, 2{sup -}, most of them bound with respect to the {sup 16}O excited 3{sup -} state. The structures are extracted as partial-wave components, as spatial sizes of matter and charge, and as probability distributions. Electromagnetic decay rates are calculated for these states. The dominating decay mode for the bound states is E2 and occasionally also M1. (orig.)
Ground and Low-Lying Collective States of Rotating Three-Boson System
Imran, Mohd.; Ahsan, M. A. H.
2016-04-01
The ground and low-lying collective states of a rotating system of N = 3 bosons harmonically confined in quasi-two-dimension and interacting via repulsive finite-range Gaussian potential is studied in weakly to moderately interacting regime. The N-body Hamiltonian matrix is diagonalized in subspaces of quantized total angular momenta 0 ≥ L ≥ 4N to obtain the ground and low-lying eigenstates. Our numerical results show that breathing modes with N-body eigenenergy spacing of 2ħω⊥, known to exist in strictly 2D system with zero-range (δ-function) interaction potential, may as well exist in quasi-2D system with finite-range Gaussian interaction potential. To gain an insight into the many-body states, the von Neumann entropy is calculated as a measure of quantum correlation and the conditional probability distribution is analyzed for the internal structure of the eigenstates. In the rapidly rotating regime the ground state in angular momentum subspaces L = (q/2)N (N - 1) with q = 2, 4 is found to exhibit the anticorrelation structure suggesting that it may variationally be described by a Bose-Laughlin like state. We further observe that the first breathing mode exhibits features similar to the Bose-Laughlin state in having eigenenergy, von Neumann entropy and internal structure independent of interaction for the three-boson system considered here. On the contrary, for eigenstates lying between the Bose-Laughlin like ground state and the first breathing mode, values of eigenenergy, von Neumann entropy and internal structure are found to vary with interaction.
R-matrix calculations for few-quark bound states
Shalchi, M. A.; Hadizadeh, M. R.
2016-10-01
The R-matrix method is implemented to study the heavy charm and bottom diquark, triquark, tetraquark, and pentaquarks in configuration space, as the bound states of quark-antiquark, diquark-quark, diquark-antidiquark, and diquark-antitriquark systems, respectively. The mass spectrum and the size of these systems are calculated for different partial wave channels. The calculated masses are compared with recent theoretical results obtained by other methods in momentum and configuration spaces and also by available experimental data.
SWKB Quantization Rules for Bound States in Quantum Wells
Sinha, A K; Sinha, Anjana; Roychoudhury, Rajkumar
2000-01-01
In a recent paper by Gomes and Adhikari (J.Phys B30 5987(1997)) a matrix formulation of the Bohr-Sommerfield quantization rule has been applied to the study of bound states in one dimension quantum wells. Here we study these potentials in the frame work of supersymmetric WKB (SWKB) quantization approximation and find that SWKB quantization rule is superior to the modified Bohr-Sommerfield or WKB rules as it exactly reproduces the eigenenergies.
Fermion Bound States Around Skyrmions in Doped Antiferromagnets
Institute of Scientific and Technical Information of China (English)
寇谡鹏
2003-01-01
We show the skyrmion effects in doped antiferromagnets for the uniform flux phase. The low-energy effective theory of the t′-J model can be mapped onto the massive quantum electrodynamics. There exist Fermion bound states around skyrmions. For each sublattice, there exist induced fractional fermion numbers around the skyrmions. The total induced fermion number is zero due to the "cancelling effect" between two sublattices with opposite charges.
R-matrix calculations for few-quark bound states
Energy Technology Data Exchange (ETDEWEB)
Shalchi, M.A. [Instituto de Fisica Teorica, UNESP, Sao Paulo, SP (Brazil); Hadizadeh, M.R. [Ohio University, Institute of Nuclear and Particle Physics and Department of Physics and Astronomy, Athens, OH (United States); Central State University, College of Science and Engineering, Wilberforce, OH (United States)
2016-10-15
The R-matrix method is implemented to study the heavy charm and bottom diquark, triquark, tetraquark, and pentaquarks in configuration space, as the bound states of quark-antiquark, diquark-quark, diquark-antidiquark, and diquark-antitriquark systems, respectively. The mass spectrum and the size of these systems are calculated for different partial wave channels. The calculated masses are compared with recent theoretical results obtained by other methods in momentum and configuration spaces and also by available experimental data. (orig.)
K¯ nuclear bound states in a dynamical model
Mareš, J.; Friedman, E.; Gal, A.
2006-05-01
A comprehensive data base of K-atom level shifts and widths is re-analyzed in order to study the density dependence of the K¯-nuclear optical potential. Significant departure from a tρ form is found only for ρ(r)/ρ ≲ 0.2 and extrapolation to nuclear-matter density ρ yields an attractive potential, about 170 MeV deep. Partial restoration of chiral symmetry compatible with pionic atoms and low-energy pion-nuclear data plays no role at the relevant low-density regime, but this effect is not ruled out at densities of order ρ and beyond. K¯-nuclear bound states are generated across the periodic table self consistently, using a relativistic mean-field model Lagrangian which couples the K¯ to the scalar and vector meson fields mediating the nuclear interactions. The reduced phase space available for K¯ absorption from these bound states is taken into account by adding an energy-dependent imaginary term which underlies the corresponding K¯-nuclear level widths, with a strength required by fits to the atomic data. Substantial polarization of the core nucleus is found for light nuclei, and the binding energies and widths calculated in this dynamical model differ appreciably from those calculated for a static nucleus. A wide range of binding energies is spanned by varying the K¯ couplings to the meson fields. Our calculations provide a lower limit of Γ=50±10 MeV on the width of nuclear bound states for K¯-binding energy in the range B˜100-200 MeV. Comments are made on the interpretation of the FINUDA experiment at DAΦNE which claimed evidence for deeply bound Kpp states in light nuclei.
Hyperons in the bound state approach with vector mesons
Schat, C L
1994-01-01
We investigate a model for hyperons based on the bound state approach in which vector mesons are explicitly incorporated. We show that for empirical values of the mesonic parameters the strange hyperon spectrum is well reproduced. We also discuss the extension of the model to heavier flavors. We show that the explicit presence of the heavy vectors leads to good predictions for the heavy baryon masses.
Lambda(1405) in the bound state soliton model
Schat, C L; Gobbi, C; Schat, C L; Scoccola, N N; Gobbi, C
1994-01-01
The strong and electromagnetic properties of the Lambda(1405) hyperon are studied in the framework of the bound state soliton model. We explicitly evaluate the strong coupling constant g(Lambda^*-N-K), the Lambda^* magnetic moment, mean square radii and radiative decay amplitudes. The results are shown to be in general agreement with available empirical data. A comparison with results of other models is also presented.
Detecting positron-atom bound states through resonant annihilation.
Dzuba, V A; Flambaum, V V; Gribakin, G F
2010-11-12
A method is proposed for detecting positron-atom bound states by observing enhanced positron annihilation due to electronic Feshbach resonances at electron-volt energies. The method is applicable to a range of open-shell transition-metal atoms which are likely to bind the positron: Fe, Co, Ni, Tc, Ru, Rh, Sn, Sb, Ta, W, Os, Ir, and Pt. Estimates of their binding energies are provided.
Detecting Positron-Atom Bound States through Resonant Annihilation
Dzuba, V. A.; Flambaum, V. V.; Gribakin, G. F.
2010-01-01
A method is proposed for detecting positron-atom bound states by observing enhanced positron annihilation due to electronic Feshbach resonances at electron-volt energies. The method is applicable to a range of open-shell transition metal atoms which are likely to bind the positron: Fe, Co, Ni, Tc, Ru, Rh, Sn, Sb, Ta, W, Os, Ir, and Pt. Estimates of their binding energies are provided.
Effects of QCD bound states on dark matter relic abundance
Liew, Seng Pei
2016-01-01
We study scenarios where there exists an exotic massive particle charged under QCD in the early Universe. We calculate the formation and dissociation rates of bound states formed by pairs of these particles, and apply the results in dark matter (DM) coannihilation scenarios, including also the Sommerfeld effect. We find that on top of the Sommerfeld enhancement, bound-state effects can further significantly increase the largest possible DM masses which can give the observed DM relic abundance, by $\\sim 30 - 100\\%$ with respect to values obtained by considering the Sommerfeld effect only, for the color triplet or octet exotic particles we consider. In particular, it indicates that the Bino DM mass in the right-handed stop-Bino coannihilation scenario in the Minimal Supersymmetric extension of the Standard Model (MSSM) can reach $\\sim 2.5$ TeV. We also apply the bound-state effects in the calculations of relic abundance of long-lived or metastable massive colored particles, and discuss the implications on the B...
Search for a bound state of kaon and pion
Kishimoto, T; Hayakawa, T; Ajimura, S; Itabashi, T; Matsuoka, K; Minami, S; Mitoma, Y; Sakaguchi, A; Shimizu, Y; Terai, K; Sato, T; Noumi, H; Sekimoto, M; Takahashi, H; Fukuda, T; Imoto, W; Mizoi, Y
2012-01-01
We have searched for a bound state of kaon and pion denoted by $X$. The $X$ was conjectured to explain the so-called $\\Theta^+$ resonance as a bound state of kaon, pion and nucleon. This model explains almost all properties of the $\\Theta^+$, however, the model works only if the $K \\pi$ interaction is strongly attractive. It is so strong that it could make a bound state $X$. Here we report a result of the search for the $X$ by using the $K^+ + N \\rightarrow X^+ + N$ reaction at P$_K\\sim$ 1.2 GeV/c. The $X^+ \\rightarrow K^+ \\gamma \\gamma$ decay produces $K^+$ in momentum region where other processes cannot fill. We observed signature of the $X^+$ with statistical significance of 2 $\\sigma$. Production cross section of $X$ with respect to that of $\\pi^0$ is 1$\\pm$0.5% if we take it as an evidence and 1.5% if we set an upper limit.
Matrix algorithms for solving (in)homogeneous bound state equations.
Blank, M; Krassnigg, A
2011-07-01
In the functional approach to quantum chromodynamics, the properties of hadronic bound states are accessible via covariant integral equations, e.g. the Bethe-Salpeter equation for mesons. In particular, one has to deal with linear, homogeneous integral equations which, in sophisticated model setups, use numerical representations of the solutions of other integral equations as part of their input. Analogously, inhomogeneous equations can be constructed to obtain off-shell information in addition to bound-state masses and other properties obtained from the covariant analogue to a wave function of the bound state. These can be solved very efficiently using well-known matrix algorithms for eigenvalues (in the homogeneous case) and the solution of linear systems (in the inhomogeneous case). We demonstrate this by solving the homogeneous and inhomogeneous Bethe-Salpeter equations and find, e.g. that for the calculation of the mass spectrum it is as efficient or even advantageous to use the inhomogeneous equation as compared to the homogeneous. This is valuable insight, in particular for the study of baryons in a three-quark setup and more involved systems.
Rapid thermal co-annihilation through bound states in QCD
Kim, Seyong; Laine, M.
2016-07-01
The co-annihilation rate of heavy particles close to thermal equilibrium, which plays a role in many classic dark matter scenarios, can be "simulated" in QCD by considering the pair annihilation rate of a heavy quark and antiquark at a temperature of a few hundred MeV. We show that the so-called Sommerfeld factors, parameterizing the rate, can be defined and measured non-perturbatively within the NRQCD framework. Lattice measurements indicate a modest suppression in the octet channel, in reasonable agreement with perturbation theory, and a large enhancement in the singlet channel, much above the perturbative prediction. The additional enhancement is suggested to originate from bound state formation and subsequent decay. Making use of a Green's function based method to incorporate thermal corrections in perturbative co-annihilation rate computations, we show that qualitative agreement with lattice data can be found once thermally broadened bound states are accounted for. We suggest that our formalism may also be applicable to specific dark matter models which have complicated bound state structures.
Doppler-shift attenuation method lifetime measurements of low-lying states in {sup 111}In
Energy Technology Data Exchange (ETDEWEB)
Bucurescu, D.; Cata-Danil, I.; Ilas, G.; Ivascu, M.; Marginean, N.; Stroe, L.; Ur, C.A. [Institute of Atomic Physics, P.O. Box MG-6, Bucharest 76900 (Romania)
1996-11-01
The lifetimes of nine low-lying excited states in {sup 111}In have been measured with the Doppler-shift attenuation method in the {sup 111}Cd({ital p},{ital n}{gamma}) reaction. A comparison of experimental quantities with predictions based on the interacting boson-fermion model unravels the states due to the coupling of a {ital g}{sub 9/2} proton hole to the quadrupole vibrations of the core. {copyright} {ital 1996 The American Physical Society.}
Bounds for State Degeneracies in 2D Conformal Field Theory
Hellerman, Simeon
2010-01-01
In this note we explore the application of modular invariance in 2-dimensional CFT to derive universal bounds for quantities describing certain state degeneracies, such as the thermodynamic entropy, or the number of marginal operators. We show that the entropy at inverse temperature 2 pi satisfies a universal lower bound, and we enumerate the principal obstacles to deriving upper bounds on entropies or quantum mechanical degeneracies for fully general CFTs. We then restrict our attention to infrared stable CFT with moderately low central charge, in addition to the usual assumptions of modular invariance, unitarity and discrete operator spectrum. For CFT in the range c_left + c_right < 48 with no relevant operators, we are able to prove an upper bound on the thermodynamic entropy at inverse temperature 2 pi. Under the same conditions we also prove that a CFT can have a number of marginal deformations no greater than ((c_left + c_right) / (48 - c_left - c_right)) e^(4 Pi) - 2.
Spectroscopy of low-lying states in neutron-deficient astatine and francium nuclei
Energy Technology Data Exchange (ETDEWEB)
Jakobsson, U., E-mail: ulrjak@kth.se; Cederwall, B. [KTH, The Division of Nuclear Physics, AlbaNova University Center, SE-10691 Stockholm (Sweden); Uusitalo, J.; Auranen, K.; Badran, H.; Cox, D. M.; Grahn, T.; Greenlees, P. T.; Julin, R.; Juutinen, S.; Herzáň, A.; Konki, J.; Leino, M.; Mallaburn, M.; Pakarinen, J.; Papadakis, P.; Partanen, J.; Rahkila, P.; Sandzelius, M.; Sarén, J. [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); and others
2015-10-15
Low-lying states in neutron-deficient astatine and francium nuclei have been studied by means of in-beam and delayed spectroscopy. The 13/2{sup +} state has been observed in francium nuclei with a similar down-sloping trend as in neighbouring astatine and bismuth isotopes, as a function of decreasing neutron number. A systematic trend can also now be seen for the 1/2{sup +} state both in astatine and francium nuclei, where the level energy decreases steeply as a function of neutron number when moving further away from the neutron shell closure. This trend is very similar between astatine nuclei and their francium isotones. Moreover, shape coexistence has been observed between the 13/2{sup +} state and the spherical 9/2{sup −} ground state in {sup 203}Fr and {sup 205}Fr.
Encrypting Majorana fermion qubits as bound states in the continuum
Guessi, L. H.; Dessotti, F. A.; Marques, Y.; Ricco, L. S.; Pereira, G. M.; Menegasso, P.; de Souza, M.; Seridonio, A. C.
2017-07-01
We theoretically investigate a topological Kitaev chain connected to a double quantum-dot (QD) setup hybridized with metallic leads. In this system we observe the emergence of two striking phenomena: (i) a decrypted Majorana fermion (MF) qubit recorded over a single QD, which is detectable by means of conductance measurements due to the asymmetrical MF-qubit leaked state into the QDs; (ii) an encrypted qubit recorded in both QDs when the leakage is symmetrical. In such a regime, we have a cryptographylike manifestation, since the MF qubit becomes bound states in the continuum, which is not detectable in conductance experiments.
Two-body bound states & the Bethe-Salpeter equation
Energy Technology Data Exchange (ETDEWEB)
Pichowsky, M. [Argonne National Lab., IL (United States); Kennedy, M. [Univ. of New Hampshire, Durham, NH (United States). Physics Dept.; Strickland, M. [Duke Univ., Durham, NC (United States)
1995-01-18
The Bethe-Salpeter formalism is used to study two-body bound states within a scalar theory: two scalar fields interacting via the exchange of a third massless scalar field. The Schwinger-Dyson equation is derived using functional and diagrammatic techniques, and the Bethe-Salpeter equation is obtained in an analogous way, showing it to be a two-particle generalization of the Schwinger-Dyson equation. The authors also present a numerical method for solving the Bethe-Salpeter equation without three-dimensional reduction. The ground and first excited state masses and wavefunctions are computed within the ladder approximation and space-like form factors are calculated.
Computational approach for calculating bound states in quantum field theory
Lv, Q. Z.; Norris, S.; Brennan, R.; Stefanovich, E.; Su, Q.; Grobe, R.
2016-09-01
We propose a nonperturbative approach to calculate bound-state energies and wave functions for quantum field theoretical models. It is based on the direct diagonalization of the corresponding quantum field theoretical Hamiltonian in an effectively discretized and truncated Hilbert space. We illustrate this approach for a Yukawa-like interaction between fermions and bosons in one spatial dimension and show where it agrees with the traditional method based on the potential picture and where it deviates due to recoil and radiative corrections. This method permits us also to obtain some insight into the spatial characteristics of the distribution of the fermions in the ground state, such as the bremsstrahlung-induced widening.
Photo-production of Bound States with Hidden Charms
Wu, Jia-Jun
2012-01-01
The photo-production of $J/\\Psi$-$^3He$ bound state ($[^3He]_{J/\\Psi}$) on a $^4He$ target has been investigated using the impulse approximation. The calculations have been performed using several $\\gamma+N \\rightarrow J/\\Psi +N$ models based on the Pomeron-exchange and accounting for the pion-exchange mechanism at low energies. The $J/\\Psi$ wavefunctions in $[^3He]_{J/\\Psi}$ are generated from various $J/\\Psi$-nucleus potentials which are constructed by either using a procedure based on the Pomeron-quark coupling mechanism or folding a $J/\\Psi$-N potential ($v_{J/\\Psi,N}$) into the nuclear densities. We consider $v_{J/\\Psi,N}$ derived from the effective field theory approach, Lattice QCD, and Pomeron-quark coupling mechanism. The upper bound of the predicted total cross sections is about $0.1 - 0.3$ pico-barn. We also consider the possibility of photo-production of a six quark-$J/\\Psi$ bound state ($[q^6]_{J/\\Psi})$ on the $^3He$ target. The Compound Bag Model of $NN$ scattering and the quark cluster model o...
Decay properties of low-lying collective states in sup 1 sup 3 sup 2 Ba
Gade, A; Meise, H; Gelberg, A; Brentano, P V
2002-01-01
The decay properties of low-lying collective states in sup 1 sup 3 sup 2 Ba were studied by means of gamma spectroscopy following the beta-decay of the 2 sup - ground state (T sub 1 sub / sub 2 =4.8 h) and a 6 sup - isomer (T sub 1 sub / sub 2 =24.3 min) of sup 1 sup 3 sup 2 La. The lanthanum nuclei were produced at the Cologne FN TANDEM accelerator using the reaction sup 1 sup 2 sup 2 Sn( sup 1 sup 4 N, 4n) sup 1 sup 3 sup 2 La. The gamma gamma coincidences and singles spectra were measured with the OSIRIS-cube spectrometer. Beside ground and quasi-gamma band many other low-lying states were observed. The gamma gamma angular correlations were analyzed to assign spins to the excited states, and to determine the multipolarities of the depopulating the gamma transitions. We also confirmed the expected dominant E2 character of transitions in the quasi-gamma band and from the quasi-gamma to the ground band but with a certain deviation: the decay 6 sup + sub 2->6 sup + sub 1 shows an unexpected large M1 fraction. ...
On the low-lying states of MgO. II
Bauschlicher, C. W., Jr.; Lengsfield, B. H., III; Silver, D. M.; Yarkony, D. R.
1981-01-01
Using a double zeta plus polarization basis set of Slater orbitals, full valence MCSCF (FVMCSCF) calculations were performed for the low-lying states of MgO. For each state the FVMCSCF calculations were used to identify the important configurations which are then used in the MCSCF calculation and subsequently as references in a single and double excitation CI calculation. This approach is found to treat all states equivalently, with the maximum error in the computed transition energies and equilibrium bond lengths of 800/cm and approximately 0.03 A, respectively. The b 3 Sigma + state which has yet to be characterized experimentally is predicted to have a transition energy of approximately 8300/cm and a bond length of 1.79 A. A spectroscopic analysis of the potential curves indicates that their shapes are in quite reasonable agreement with the range of experimental results.
On the low-lying states of MgO. II
Bauschlicher, C. W., Jr.; Lengsfield, B. H., III; Silver, D. M.; Yarkony, D. R.
1981-01-01
Using a double zeta plus polarization basis set of Slater orbitals, full valence MCSCF (FVMCSCF) calculations were performed for the low-lying states of MgO. For each state the FVMCSCF calculations were used to identify the important configurations which are then used in the MCSCF calculation and subsequently as references in a single and double excitation CI calculation. This approach is found to treat all states equivalently, with the maximum error in the computed transition energies and equilibrium bond lengths of 800/cm and approximately 0.03 A, respectively. The b 3 Sigma + state which has yet to be characterized experimentally is predicted to have a transition energy of approximately 8300/cm and a bond length of 1.79 A. A spectroscopic analysis of the potential curves indicates that their shapes are in quite reasonable agreement with the range of experimental results.
K- and p¯ deeply bound atomic states
Friedman, E.; Gal, A.
1999-12-01
The strongly absorptive optical potentials Vopt which have been deduced from the strong-interaction level shifts and widths in X-ray spectra of K- and p¯ atoms produce effective repulsion leading to substantial suppression of the atomic wave functions within the nucleus. The width of atomic levels then saturates as function of the strength of Im Vopt. We find that `deeply bound' atomic states, which are inaccessible in the atomic cascade process, are generally narrow, due to this mechanism, over the entire periodic table and should be reasonably well resolved. These predictions are insensitive to Vopt, provided it was fitted to the observed X-ray spectra. In contrast, the nuclear states bound by Vopt are very broad and their spectrum depends sensitively on details of Vopt. We discuss production reactions for K- atomic states using slow K- mesons from the decay of the φ(1020) vector meson, and the ( p¯,p ) reaction for p¯ atomic states. Rough cross section estimates are given.
Forbidden Transition Probabilities of Astrophysical Interest among Low-lying States of V III
Indian Academy of Sciences (India)
Andrei Irimia
2007-06-01
Electric and magnetic multipole transitions among low-lying states of doubly ionized vanadium were computed using the multi-configuration Hartree–Fock (MCHF) method with Breit–Pauli (BP) corrections to a non-relativistic Hamiltonian. Energy levels were determined up to and including 32(1)4 b 27/2 and computed energies were found to be in good agreement with experiment and other theories. In addition to Einstein coefficients for some E2 and M1 transitions, lifetime data and selected weighted oscillator strengths are also reported.
Directory of Open Access Journals (Sweden)
Mohammad Shahzad
2016-05-01
Full Text Available This study deals with the control of chaotic dynamics of tumor cells, healthy host cells, and effector immune cells in a chaotic Three Dimensional Cancer Model (TDCM by State Space Exact Linearization (SSEL technique based on Lie algebra. A non-linear feedback control law is designed which induces a coordinate transformation thereby changing the original chaotic TDCM system into a controlled one linear system. Numerical simulation has been carried using Mathematica that witness the robustness of the technique implemented on the chosen chaotic system.
Proton core polarization in low-lying states of 86Sr
Connelly, J. P.; Milliman, T. E.; Heisenberg, J. H.; Hersman, F. W.; Wise, J. E., III; Papanicolas, C. N.
1990-11-01
Electron-scattering cross sections, measured between 0.4 and 3.1 fm-1, have been unfolded to obtain charge transition densities for the low-lying 2+, 4+, 6+, and 8+ states in 86Sr. A comparison is made to analogous levels in 92Mo. Angular momentum recoupling in the 1g9/2 shell of two protons in 92Mo and two neutron holes in 86Sr are the dominant configurations for these levels. Proton core polarization in 86Sr neutron valence transitions diminishes with increasing multipolarity, indicating the residual interaction weakens with increasing momentum transfer.
Electron impact excitation and assignment of the low-lying electronic states of CO2
Hall, R. I.; Trajmar, S.
1973-01-01
Electron scattering spectra of CO2 are reported in the 7 to 10 eV energy-loss range, at energies of 0.2, 0.35, 0.6, 0.7, and 7.0 eV above threshold, and at a scattering angle of 90 deg. Several new distinct overlapping continua with weak, diffuse bands superimposed are observed to lie in this energy-loss range. The experimental spectra are discussed in the light of recent ab initio configuration-interaction calculations of the vertical transition energies of CO2. The experimental spectra are shown to be consistent with the excitation states of CO2.
Bacalis, Naoum C
2016-01-01
The computation of small concise and comprehensible excited state wave functions is needed because many electronic processes occur in excited states. But since the excited energies are saddle points in the Hilbert space of wave functions, the standard computational methods, based on orthogonality to lower lying approximants, resort to huge and incomprehensible wave functions, otherwise, the truncated wave function is veered away from the exact. The presented variational principle for excited states, Fn, is demonstrated to lead to the correct excited eigenfunction in necessarily small truncated spaces. Using Hylleraas coordinates for He 1S 1s2s, the standard method based on the theorem of Hylleraas - Unheim, and MacDonald, yields misleading main orbitals 1s1s' and needs a series expansion of 27 terms to be corrected, whereas minimizing Fn goes directly to the corect main orbitals, 1s2s, and can be adequately improved by 8 terms. Fn uses crude, rather inaccurate, lower lying approximants and does not need ortho...
Zhang, Xiaomei; Liu, Xiaoting; Liang, Guiying; Li, Rui; Xu, Haifeng; Yan, Bing
2016-01-01
The potential energy curves (PECs) of the 22 Λ-S states of the phosphorus monoiodide (PI) molecule have been calculated at the level of MRCI+Q method with correlation-consistent quadruple-ζ quality basis set. The spectroscopic constants of the bound states are determined, which well reproduce the available measurements. The metastable a1Δ state has been reported for the first time, which lies between the X3Σ- and b1Σ+ states and have much deeper well than the ground state. The R-dependent spin-orbit (SO) matrix elements are calculated with the full-electron Breit-Pauli operator. Based on the SO matrix elements, the perturbations that the 23Π state may suffer from are analyzed in detail. The SOC effect makes the original Λ-S states split into 51 Ω states. In the zero-field splitting of the ground state X3Σ-, the spin-spin coupling contribution (2.23 cm-1) is found to be much smaller compared to the spin-orbit coupling contribution (50 cm-1). The avoided crossings between the Ω states lead to much shallower potential wells and the change of dissociation relationships of the states. The Ω-state wavefunctions are analyzed depending on their Λ-S compositions, showing the strong interactions among several quasidegenerate Λ-S states of the same total SO symmetry. The transition properties including electric dipole (E1), magnetic dipole (M1), and electric quadrupole (E2) transition moments (TMs), the Franck-Condon factors, the transition probabilities and the radiative lifetimes are computed for the transitions between Ω components of a1Δ and b1Σ+ states and ground state. The transition probabilities induced by the E1, E2, and M1 transitions are evaluated. The E2 makes little effect on transition probabilities. In contrast, the E1 transition makes the main contribution to the transition probability and the M1 transition also brings the influence that cannot be neglected. Finally, the radiative lifetimes are determined with the transition moments including E
Characterization of the low-lying 0$^{+}$ and 2$^{+}$ states of $^{68}$ Ni
Recently, a number of low-lying low-spin states have been firmly identified in $^{68}$Ni; the position of the first excited state (which is a 0$^{+}$ state), the spin and parity of the second excited 0$^{+}$ state and the spin and parity of the second and third 2$^+$ states have been fixed. The identification of these three pairs of 0$^+$ and 2$^+$ states in $^{68}$Ni (Z=28 and N=40) forms ideal tests to validate shell-model calculations and the effective interactions developed for the nickel region but also hints to triple shape coexistence including even strongly deformed structures. The aim of this proposal is to collect detailed spectroscopic data of the low-spin states of $^{68}$Ni (Z=28, N=40) in order to characterize these triple pairs of 0$^+$ and 2$^+$ states. $\\gamma$-branching ratios of the 0$^+$ and 2$^+$ states and the E0 transition strengths as well as the E2 transition rate of the 0$_3^+$ will be obtained using the new ISOLDE decay station that is constructed from an efficient array of germaniu...
Low-lying continuum states of drip-line Oxygen isotopes
Tsukiyama, Koshiroh; Fujimoto, Rintaro
2010-01-01
Low-lying continuum states of exotic oxygen isotopes are studied, by introducing the Continuum-Coupled Shell Model (CCSM) characterized by an infinite wall placed very far and by an interaction for continuum coupling constructed in a close relation to realistic shell-model interaction. Neutron emission spectra from exotic oxygen isotopes are calculated by the doorway-state approach in heavy-ion multi-nucleon transfer reactions. The results agree with experiment remarkably well, as an evidence that the continuum effects are stronger than $\\sim$1 MeV, consistently with the shell evolution in exotic nuclei. The results by this CCSM doorway-state approach are compared with calculations on neutron-scattering resonance peaks made within the CCSM phase-shift approach and also with those obtained in the Gamow shell model, by taking the same interaction. Remarkable similarities in peak energies and certain differences in widths are then obtained.
alpha. - d resonances and the low-lying states of sup 6 Li
Energy Technology Data Exchange (ETDEWEB)
Eskandarian, A.; Afnan, I.R. (School of Physical Sciences, The Flinders University of South Australia, Bedford Park, South Australia 5042 (Australia))
1992-12-01
The low-lying states (below the {sup 3}He-{sup 3}H threshold) of the {sup 6}Li nucleus are generated using three-body models with two-body nonlocal separable interactions between the constituent particles. The positions and widths of the states are determined by searching for the eigenvalues of the kernel of the Faddeev equations in the complex energy plane. When appropriate (for {ital T}=0 states only), the results are compared with a separate determination of these quantities from the {alpha}-{ital d} scattering process. All experimentally observed levels are found. Given that the Coulomb interaction is not included in our calculations, agreement with experiment is favorable for both the positions and the widths of the resonances.
α-d resonances and the low-lying states of 6Li
Eskandarian, A.; Afnan, I. R.
1992-12-01
The low-lying states (below the 3-3H threshold) of the 6Li nucleus are generated using three-body models with two-body nonlocal separable interactions between the constituent particles. The positions and widths of the states are determined by searching for the eigenvalues of the kernel of the Faddeev equations in the complex energy plane. When appropriate (for T=0 states only), the results are compared with a separate determination of these quantities from the α-d scattering process. All experimentally observed levels are found. Given that the Coulomb interaction is not included in our calculations, agreement with experiment is favorable for both the positions and the widths of the resonances.
Performance of Hyperspherical Harmonic Expansionon the Low-lying Pand D States of Helium Atom
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
The wave functions of the n 1,3P (n=2,3,4) and the n 1,3D (n=3,4,5) low-lying states ofthe helium atom are expanded into the complete sets of the symmetrically adapted basis functionsfrom hyperspherical harmonic functions in the angle part and of generalized Laguerre functions inthe radial part respectively, and are then augmented by the simplest type of Jastrow correlationfactor to incorporate electron-nucleus cusp only. The excellent agreement between the presentnonrelativistic eigen-energies and those from the sophisticated configuration interaction (CI)method for the examined states indicates that the hyperspherical harmonic method can also be applied to the P and the D excited states of the helium atom.
Static and dynamic properties of QCD bound states
Energy Technology Data Exchange (ETDEWEB)
Kubrak, Stanislav
2015-07-01
The QCD phenomenology can be faced with the framework of the coupled quark DSE, meson BSE and baryon Faddeev equation, providing non-perturbative, continuum and Poincare invariant scientific approach. The research performed throughout this thesis is twofold. From one perspective we focus on the investigation of mass spectra for mesons with total spin quantum number J=3 and arising Regge-trajectory for natural parity states J{sup PC}=1{sup --},2{sup ++},3{sup --} within rainbow-ladder single gluon exchange model. The other findings are concerning the impact of the pion cloud effect on J>2 meson states, baryon masses, namely on Nucleon and Delta three-body bound states and meson dynamical properties like the pion form factor.
The relativistic bound states of a non-central potential
Indian Academy of Sciences (India)
MAHDI ESHGHI; HOSSEIN MEHRABAN; SAMEER MIKHDAIR
2017-04-01
We investigate the relativistic effects of a moving particle in the field of a pseudoharmonic oscillatory ring-shaped potential under the spin and pseudospin symmetric Dirac wave equation. We obtain the bound-state energy eigenvalue equation and the corresponding two-components spinor wave functions by using the formalism of supersymmetric quantum mechanics (SUSYQM). Furthermore, the non-relativistic limits are obtained by simply making a proper replacement of parameters. The thermodynamic properties are also studied. Our numerical results for the energy eigenvalues are also presented.
Resonantly Trapped Bound State in the Continuum Laser
Lepetit, Thomas; Kodigala, Ashok; Bahari, Babak; Fainman, Yeshaiahu; Kanté, Boubacar
2015-01-01
Cavities play a fundamental role in wave phenomena from quantum mechanics to electromagnetism and dictate the spatiotemporal physics of lasers. In general, they are constructed by closing all "doors" through which waves can escape. We report, at room temperature, a bound state in the continuum laser that harnesses optical modes residing in the radiation continuum but nonetheless may possess arbitrarily high quality factors. These counterintuitive cavities are based on resonantly trapped symmetry-compatible modes that destructively interfere. Our experimental demonstration opens exciting avenues towards coherent sources with intriguing topological properties for optical trapping, biological imaging, and quantum communication.
R-Matrix Calculations for Few-Quark Bound States
Shalchi, M A
2016-01-01
The R-matrix method is implemented to study the heavy charm and bottom diquark, triquark, tetraquark and pentaquarks in configuration space, as the bound states of quark-antiquark, diquark-quark, diquark-antidiquark and diquark-antitriquark systems, respectively. The mass spectrum and the size of these systems are calculated for different partial wave channels. The calculated masses are compared with recent theoretical results obtained by %the solution of Lippmann-Schwinger equation other methods in momentum and configuration spaces and also by available experimental data.
Diquark bound states at far beyond ladder truncation
Jinno, Ryusuke; Mishima, Go
2015-01-01
The Bethe-Salpeter equation in the diquark channel is investigated by employing the Dyson-Schwinger method together with the Munczek-Nemirovsky model. The novelty of our study is a resummation of completely-crossed ladder diagrams in the Bethe-Salpeter kernel. These diagrams are enhanced due to their color factors in the diquark channel, but not in the meson channel. As a result of our analysis, it is suggested that diquark bound-state solutions exist in the Bethe-Salpeter equation, which have been thought to be absent.
Stieltjes electrostatic model interpretation for bound state problems
Indian Academy of Sciences (India)
K V S Shiv Chaitanya
2014-07-01
In this paper, it is shown that Stieltjes electrostatic model and quantum Hamilton Jacobi formalism are analogous to each other. This analogy allows the bound state problem to mimic as unit moving imaginary charges $i\\hbar$, which are placed in between the two fixed imaginary charges arising due to the classical turning points of the potential. The interaction potential between unit moving imaginary charges $i\\hbar$ is given by the logarithm of the wave function. For an exactly solvable potential, this system attains stable equilibrium position at the zeros of the orthogonal polynomials depending upon the interval of the classical turning points.
Scattering and Bound States of a Deformed Quantum Mechanics
Ching, Chee-Leong
2012-01-01
We construct the exact position representation of a deformed quantum mechanics which exhibits an intrinsic maximum momentum and use it to study problems such as a particle in a box and scattering from a step potential, among others. In particular, we show that unlike usual quantum mechanics, the present deformed case delays the formation of bound states in a finite potential well. In the process we also highlight some limitations and pit-falls of low-momentum or perturbative treatments and thus resolve two puzzles occurring in the literature.
Quarkonium-nucleus bound states from lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Beane, S. R. [Univ. of Washington, Seattle, WA (United States); Chang, E. [Univ. of Washington, Seattle, WA (United States); Cohen, S. D. [Univ. of Washington, Seattle, WA (United States); Detmold, W. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Lin, H. -W. [Univ. of Washington, Seattle, WA (United States); Orginos, K. [College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Parreño, A. [Univ., de Barcelona, Marti Franques (Spain); Savage, M. J. [Univ. of Washington, Seattle, WA (United States)
2015-06-11
Quarkonium-nucleus systems are composed of two interacting hadronic states without common valence quarks, which interact primarily through multi-gluon exchanges, realizing a color van der Waals force. We present lattice QCD calculations of the interactions of strange and charm quarkonia with light nuclei. Both the strangeonium-nucleus and charmonium-nucleus systems are found to be relatively deeply bound when the masses of the three light quarks are set equal to that of the physical strange quark. Extrapolation of these results to the physical light-quark masses suggests that the binding energy of charmonium to nuclear matter is B < 40 MeV.
Are $\\eta$- and $\\omega$-nuclear states bound ?
Tsushima, K; Thomas, A W; Saitô, K
1998-01-01
We investigate theoretically whether it is feasible to detect $\\eta$- and $^{40}$Ca, $^{90}$Zr and $^{208}$Pb, we also investigate $^6$He, $^{11}$B and $^{26}$Mg, which are the final nuclei in the proposed experiment involving the (d,$^3$He) reaction at GSI. Potentials for the $\\eta$ and $\\omega$ mesons in these nuclei are calculated in local density approximation, embedding the mesons in the nucleus described by solving the mean-field equations of motion in the QMC model. Our results suggest that one should expect to find $\\eta$- and $\\omega$-nucleus bound states in all these nuclei.
Exotic Hadron Bound State Production at Hadronic Colliders
Jin, Yi; Liu, Yan-Rui; Meng, Lu; Si, Zon-Guo; Zhang, Xiao-Feng
2016-01-01
The non-relativistic wave function framework is applied to study the production and decay of the exotic hadrons which can be effectively described as bound states of other hadrons. The ingredient hadron production can be calculated by event generators. We investigate the production of exotic hadrons in the multiproduction processes at high energy hadronic colliders with the help of the event generators. We illustrate the crucial information such as their momentum distributions and production rate for the measurements at the large hadron collider. This study provides crucial information for the measurements of the relevant exotic hadrons.
Understanding close-lying exotic charmonia states within QCD sum rules
Martínez Torres, A.; Khemchandani, K. P.; Dias, J. M.; Navarra, F. S.; Nielsen, M.
2017-10-01
Motivated by the experimental findings of some new exotic states decaying into channels like J / ψϕ, we investigate the formation of resonances/bound states in the Ds* Dbars* system using QCD sum rules. To do this we start with a current of the type vector times vector and use spin projectors to separate the spin 0, 1 and 2 contributions to the correlation function. We find three states with isospin 0, nearly spin degenerate, with a mass around 4.1 GeV. We have also investigated the decay of these states to J / ψϕ and provide the corresponding partial widths. Such information should be useful for experimental studies in future.
Ab initio study of the low-lying electronic states of the CaO molecule
Energy Technology Data Exchange (ETDEWEB)
Khalil, Hossain; Brites, Vincent; Quere, Frederic Le [Universite Paris-Est, Laboratoire de Modelisation et Simulation Multi Echelle, UMR 8208 CNRS, Batiment Lavoisier, 5 boulevard Descartes, Champs sur Marne, 77454 Marne-la-Vallee, Cedex 2 (France); Leonard, Celine, E-mail: celine.leonard@univ-paris-est.fr [Universite Paris-Est, Laboratoire de Modelisation et Simulation Multi Echelle, UMR 8208 CNRS, Batiment Lavoisier, 5 boulevard Descartes, Champs sur Marne, 77454 Marne-la-Vallee, Cedex 2 (France)
2011-07-28
Graphical abstract: Highly correlated ab initio calculations have been performed for an accurate determination of the electronic structure of the low-lying electronic states of the CaO molecule. The computations are done using the aug-cc-pV5Z basis set for O and the cc-pCV5Z for Ca. The potential energy curves for the molecular states correlating to the lowest three asymptotes are calculated at the CASSCF level. The potential curves of the lowest five molecular states, X{sup 1}{Sigma}{sup +}, a{sup 3}{Pi}, A'{sup 1{Pi}}, b{sup 3}{Sigma}{sup +} and A{sup 1}{Sigma}{sup +}, and the corresponding dipole moment functions have been determined using internally contracted multi-reference configuration interaction approaches. The spectroscopic constants associated with these electronic states are compared to experimental values. The corresponding electronic wavefunctions have also been analyzed using the dipole moment functions. Display Omitted Highlights: {yields} The five lowest electronic states of Cao have been determined ab initio at a high level of accuracy. {yields} Large active space, core-valence correlation and configuration interaction are required. {yields} The multi-configurational nature of the electronic ground state is confirmed as well as its monovalent and divalent ionic nature using dipole moment analysis. {yields} These interacting potentials will serve for future obtention of spin-rovibronic levels. - Abstract: Highly correlated ab initio calculations have been performed for an accurate determination of the electronic structure of the low-lying electronic states of the CaO molecule. The computations are done using the aug-cc-pV5Z basis set for O and the cc-pCV5Z for Ca. The potential energy curves for the molecular states correlating to the lowest three asymptotes are calculated at the CASSCF level. The potential curves of the lowest five molecular states, X{sup 1}{Sigma}{sup +}, a{sup 3}{Pi}, A'{sup 1}{Pi}, b{sup 3}{Sigma}{sup +} and A{sup 1
Fingerprints of Majorana Bound States in Aharonov-Bohm Geometry
Tripathi, Krashna Mohan; Das, Sourin; Rao, Sumathi
2016-04-01
We study a ring geometry, coupled to two normal metallic leads, which has a Majorana bound state (MBS) embedded in one of its arms and is threaded by Aharonov-Bohm (A B ) flux ϕ . We show that by varying the A B flux, the two leads go through resonance in an anticorrelated fashion while the resonance conductance is quantized to 2 e2/h . We further show that such anticorrelation is completely absent when the MBS is replaced by an Andreev bound state (ABS). Hence this anti-correlation in conductance when studied as a function of ϕ provides a unique signature of the MBS which cannot be faked by an ABS. We contrast the phase sensitivity of the MBS and ABS in terms of tunneling conductances. We argue that the relative phase between the tunneling amplitude of the electrons and holes from either lead to the level (MBS or ABS), which is constrained to 0 ,π for the MBS and unconstrained for the ABS, is responsible for this interesting contrast in the A B effect between the MBS and ABS.
Ultrafast dynamics of the lowest-lying neutral states in carbon dioxide
Wright, Travis W.; Champenois, Elio G.; Cryan, James P.; Shivaram, Niranjan; Yang, Chan-Shan; Belkacem, Ali
2017-02-01
We present a study of the ultrafast dissociation dynamics of the lowest-lying electronic excited states in CO2 by using ultraviolet (UV) and extreme-ultraviolet (XUV) pulses from high-order harmonic generation. We observe two primary dissociation channels: a direct dissociation channel along the Π1g electronically excited manifold, and a second channel which results from the mixing of electronic states. The direct dissociation channel is found to have a lifetime which is shorter than our experimental resolution, whereas the second channel has a significantly longer lifetime of nearly 200 fs. In this long-lived channel we observe a beating of the vibrational populations with a period of ˜133 fs.
Electron-impact excitation of the low-lying electronic states of formaldehyde
Chutjian, A.
1974-01-01
Electron-impact excitation has been observed at incident electron energies of 10.1 and 20.1 eV to the first five excited electronic states of formaldehyde lying at and below the 1B2 state at 7.10 eV. These excitations include two new transitions in the energy-loss range 5.6-6.2 eV and 6.7-7.0 eV which have been detected for the first time, either through electron-impact excitation or photon absorption. The differential cross sections of these new excitations are given at scattering angles between 15 and 135 deg. These cross-section ratios peak at large scattering angles - a characteristic of triplet - singlet excitations. The design and performance of the electron-impact spectrometer used in the above observations is outlined and discussed.
Decay of Bethe-Salpeter kernel and bound states for the lattice four Fermi model
Energy Technology Data Exchange (ETDEWEB)
Anjos, Petrus Henrique Ribeiro dos [Universidade Federal de Goias (UFG), Goiania, GO (Brazil)
2012-07-01
Full text: We consider an imaginary-time functional integral formulation of the the lattice four-Fermi or Gross-Neveu model in d + 1 space-time dimensions (d = 1, 2, 3) and with N-component fermions. Let 0 < {kappa} << 1 be the hopping parameter, {lambda} > 0 the four-fermion coupling, m > 0 the bare fermion mass and take s x s spin matrices (s = 2,4). In a previous work, we derive spectral representations for two- and four- point correlation functions and use this result to show that the low-lying energy-momentum spectrum of this model exhibits isolated dispersion curves which are identified as single particles, multi-particle bands and bound states. In this previous analysis, the one-particle energy-momentum spectrum is obtained rigorously and is manifested by sN/2 isolated and identical dispersion curves, and the mass of particles has asymptotic value order of order 1n {kappa}. The existence of two-particle bound states above or below the two-particle band depends on whether Gaussian domination does hold or does not, respectively. Two-particle bound states emerge from solutions to a lattice Bethe-Salpeter equation that we solve in a ladder approximation. Within this approximation, the bound states have O({kappa}{sup 0}) binding energies at zero system momentum and their masses are all equal, with value {approx} -2 1n {kappa}. In this work, using the hyperplane decoupling method, we provide a detailed analysis of the decay of the Bethe-Salpeter kernel and show how to use this decay to extend the spectral result obtained in the ladder approximation to the full model. In particular, we prove that if the two-point function decays faster than the four-point function (Gaussian subjugation) then the only point in the mass spectrum above the one-particle mass and below the two-particle band is the bound state mass. (author)
Lower Bound for entanglement cost of antisymmetric states
Shimono, T
2002-01-01
This report gives a lower bound of entanglement cost for antisymmetric states of bipartite d-level systems to be log_2 (d/(d-1)) ebit (for d=3, E_c >= 0.585...). The paper quant-ph/0112131 claims that the value is equal to one ebit for d=3, since all of the eigenvalues of reduced matrix of any pure states living in N times tensor product of antisymmetric space is not greater than 2^(-N) thus the von Neumann entropy is not less than N, but the proof is not true. Hence whether the value is equal to or less than one ebit is not clear at this moment.
Bound states for non-symmetric evolution Schroedinger potentials
Energy Technology Data Exchange (ETDEWEB)
Corona, Gulmaro Corona [Area de Analisis Matematico y sus Aplicaciones, Universidad Autonoma Metropolitana-Azcapotalco, Atzcapotzalco, DF (Mexico)). E-mail: ccg@correo.azc.uam.mx
2001-09-14
We consider the spectral problem associated with the evolution Schroedinger equation, (D{sup 2}+ k{sup 2}){phi}=u{phi}, where u is a matrix-square-valued function, with entries in the Schwartz class defined on the real line. The solution {phi}, called the wavefunction, consists of a function of one real variable, matrix-square-valued with entries in the Schwartz class. This problem has been dealt for symmetric potentials u. We found for the present case that the bound states are localized similarly to the scalar and symmetric cases, but by the zeroes of an analytic matrix-valued function. If we add an extra condition to the potential u, we can determine these states by an analytic scalar function. We do this by generalizing the scalar and symmetric cases but without using the fact that the Wronskian of a pair of wavefunction is constant. (author)
Three-nucleon bound states using realistic potential models
Nogga, A.; Kievsky, A.; Kamada, H.; Glöckle, W.; Marcucci, L. E.; Rosati, S.; Viviani, M.
2003-03-01
The bound states of 3H and 3He have been calculated by using the Argonne v18 plus the Urbana IX three-nucleon potential. The isospin T=3/2 state have been included in the calculations as well as the n-p mass difference. The 3H-3He mass difference has been evaluated through the charge-dependent terms explicitly included in the two-body potential. The calculations have been performed using two different methods: the solution of the Faddeev equations in momentum space and the expansion on the correlated hyperspherical harmonic basis. The results are in agreement within 0.1% and can be used as benchmark tests. Results for the charge-dependent Bonn interaction in conjunction with the Tucson-Melbourne three-nucleon force are also presented. It is shown that the 3H and 3He binding energy difference can be predicted model independently.
The three-nucleon bound state using realistic potential models
Nogga, A; Kamada, H; Glöckle, W; Marcucci, L E; Rosati, S; Viviani, M
2003-01-01
The bound states of $^3$H and $^3$He have been calculated using the Argonne $v_{18}$ plus the Urbana three-nucleon potential. The isospin $T=3/2$ state have been included in the calculations as well as the $n$-$p$ mass difference. The $^3$H-$^3$He mass difference has been evaluated through the charge dependent terms explicitly included in the two-body potential. The calculations have been performed using two different methods: the solution of the Faddeev equations in momentum space and the expansion on the correlated hyperspherical harmonic basis. The results are in agreement within 0.1% and can be used as benchmark tests. Results for the CD-Bonn interaction are also presented. It is shown that the $^3$H and $^3$He binding energy difference can be predicted model independently.
Quantum state discrimination bounds for finite sample size
Audenaert, Koenraad M R; Verstraete, Frank
2012-01-01
In the problem of quantum state discrimination, one has to determine by measurements the state of a quantum system, based on the a priori side information that the true state is one of two given and completely known states, rho or sigma. In general, it is not possible to decide the identity of the true state with certainty, and the optimal measurement strategy depends on whether the two possible errors (mistaking rho for sigma, or the other way around) are treated as of equal importance or not. Recent results on the quantum Chernoff and Hoeffding bounds show that, if several copies of the system are available then the optimal error probabilities decay exponentially in the number of copies, and the decay rate is given by a certain statistical distance between rho and sigma (the Chernoff distance and the Hoeffding distances, respectively). While these results provide a complete solution for the asymptotic problem, they are not completely satisfying from a practical point of view. Indeed, in realistic scenarios ...
Highly charged ions in Penning traps, a new tool for resolving low lying isomeric states
Gallant, A T; Brunner, T; Chowdhury, U; Ettenauer, S; Simon, V V; Mané, E; Simon, M C; Andreoiu, C; Delheij, P; Gwinner, G; Pearson, M R; Ringle, R; Dilling, J
2011-01-01
The use of highly charged ions greatly increases the precision and resolving power, in particular for short-lived species produced at on-line radio-isotope beam facilities, achievable with Penning trap mass spectrometers. This increase in resolving power provides a new and unique access to resolving low-lying long-lived ($T_{1/2} > 50$ ms) nuclear isomers. Recently, the $111.19(22)$ keV (determined from $\\gamma$-ray spectroscopy) isomeric state in $^{78}$Rb has been resolved from the ground state, in a charge state of $q=8+$ with the TITAN Penning trap at the TRIUMF-ISAC facility. The energy level of the isomer was measured to be $108.7(6.4)$ keV above the ground state. The extracted masses for both the ground and isomeric states, and their difference, agree with the AME2003 and Nuclear Data Sheet values. This proof of principle measurement demonstrates the feasibility of using Penning trap mass spectrometers coupled to charge breeders to study nuclear isomers and opens a new route for isomer searches.
Lasing action from photonic bound states in continuum
Kodigala, Ashok; Lepetit, Thomas; Gu, Qing; Bahari, Babak; Fainman, Yeshaiahu; Kanté, Boubacar
2017-01-01
In 1929, only three years after the advent of quantum mechanics, von Neumann and Wigner showed that Schrödinger’s equation can have bound states above the continuum threshold. These peculiar states, called bound states in the continuum (BICs), manifest themselves as resonances that do not decay. For several decades afterwards the idea lay dormant, regarded primarily as a mathematical curiosity. In 1977, Herrick and Stillinger revived interest in BICs when they suggested that BICs could be observed in semiconductor superlattices. BICs arise naturally from Feshbach’s quantum mechanical theory of resonances, as explained by Friedrich and Wintgen, and are thus more physical than initially realized. Recently, it was realized that BICs are intrinsically a wave phenomenon and are thus not restricted to the realm of quantum mechanics. They have since been shown to occur in many different fields of wave physics including acoustics, microwaves and nanophotonics. However, experimental observations of BICs have been limited to passive systems and the realization of BIC lasers has remained elusive. Here we report, at room temperature, lasing action from an optically pumped BIC cavity. Our results show that the lasing wavelength of the fabricated BIC cavities, each made of an array of cylindrical nanoresonators suspended in air, scales with the radii of the nanoresonators according to the theoretical prediction for the BIC mode. Moreover, lasing action from the designed BIC cavity persists even after scaling down the array to as few as 8-by-8 nanoresonators. BIC lasers open up new avenues in the study of light-matter interaction because they are intrinsically connected to topological charges and represent natural vector beam sources (that is, there are several possible beam shapes), which are highly sought after in the fields of optical trapping, biological sensing and quantum information.
Low-Lying Resonance States of Slow Electron Collisions With Atomic Oxygen
Institute of Scientific and Technical Information of China (English)
吴建华; 袁建民
2003-01-01
A 39-target state close-coupling calculation of low-energy electron scattering from atomic oxygen is carried out with core-valence electron correlation by using R-matrix method. It is shown that the elastic cross section has a huge and sharp increase with the electron energy going down below 1eV. This remarkable structure is attributed to a few very low-lying potential resonances and the features of these resonances are given with partial cross sections. It is also shown that after considering excitations of two electrons from 2s shell, the three lowest atomic energy levels are in agreement with experimental results better than that just considering excitations of two electrons from the 2p shell as well as only one electron from the 2s shell. Elastic and two excitation (3P → 1 D and 3p → 1S) cross sections are given and compared with the other theoretical and experimental results.
Universal bounds on charged states in 2d CFT and 3d gravity
Energy Technology Data Exchange (ETDEWEB)
Benjamin, Nathan; Dyer, Ethan [Stanford Institute for Theoretical Physics, Via Pueblo, Stanford, CA, 94305 (United States); Fitzpatrick, A. Liam [Boston University Physics Department, Commonwealth Avenue, Boston, MA, 02215 (United States); Kachru, Shamit [Stanford Institute for Theoretical Physics, Via Pueblo, Stanford, CA, 94305 (United States)
2016-08-04
We derive an explicit bound on the dimension of the lightest charged state in two dimensional conformal field theories with a global abelian symmetry. We find that the bound scales with c and provide examples that parametrically saturate this bound. We also prove that any such theory must contain a state with charge-to-mass ratio above a minimal lower bound. We comment on the implications for charged states in three dimensional theories of gravity.
Universal Bounds on Charged States in 2d CFT and 3d Gravity
Benjamin, Nathan; Fitzpatrick, A Liam; Kachru, Shamit
2016-01-01
We derive an explicit bound on the dimension of the lightest charged state in two dimensional conformal field theories with a global abelian symmetry. We find that the bound scales with $c$ and provide examples that parametrically saturate this bound. We also prove than any such theory must contain a state with charge-to-mass ratio above a minimal lower bound. We comment on the implications for charged states in three dimensional theories of gravity.
Olsen, Seth; Schwarzer, Dirk; Troe, Jürgen; Smith, Sean C
2010-04-01
Recent experiments have revealed the existence of an excited state dissociative mechanism for certain peroxycarbonates, with the demonstration that the lifetime of the excited state matches the picosecond time scale for appearance of nascent carbon dioxide product. The data infer that the photoreaction proceeds via an effectively concerted three-body dissociation within the lifetime of the singlet excited state. Many other arylperoxides decay sequentially via [(aryloxy)carbonyl]oxy radical intermediates on nanosecond-microsecond time scales. Uncertainty as to the lifetime of the excited state relates to the character and the relative energetic ordering of states of the parent molecule, since the spectra and photochemistry imply that low-lying states may exist on each of the aryl, carbonate, and peroxide chemical functionalities. We employ many-body electronic structure calculations to determine the energies and characters of the low-lying valence states of a minimal aryl peroxycarbonate model germane to the above-mentioned experiments, methyl phenyl peroxycarbonate (MPC). Our results indicate that the lowest-lying state is an intrinsically nondissociative aryl pipi* excited state. We identify additional low-lying states that are expected to be dissociative in nature and propose that the time scales observed for the dissociation reaction may correspond to the time scale for transfer of excited state population to these states.
Weakly bound states with spin-isospin symmetry
Kievsky, A.; Gattobigio, M.
2016-03-01
We discuss weakly bound states of a few-fermion system having spin-isospin symmetry. This corresponds to the nuclear physics case in which the singlet, a0, and triplet, a1, n - p scattering lengths are large with respect to the range of the nuclear interaction. The ratio of the two is about a0/a1 ≈ -4.31. This value defines a plane in which a0 and a1 can be varied up to the unitary limit, 1/a0 = 0 and 1/a1 = 0, maintaining its ratio fixed. Using a spin dependant potential model we estimate the three-nucleon binding energy along that plane. This analysis can be considered an extension of the Efimov plot for three bosons to the case of three 1/2-spin-isospin fermions.
Weakly bound states with spin-isospin symmetry
Kievsky, A
2015-01-01
We discuss weakly bound states of a few-fermion system having spin-isospin symmetry. This corresponds to the nuclear physics case in which the singlet, $a_0$, and triplet, $a_1$, $n-p$ scattering lengths are large with respect to the range of the nuclear interaction. The ratio of the two is about $a_0/a_1\\approx-4.31$. This value defines a plane in which $a_0$ and $a_1$ can be varied up to the unitary limit, $1/a_0=0$ and $1/a_1=0$, maintaining its ratio fixed. Using a spin dependant potential model we estimate the three-nucleon binding energy along that plane. This analysis can be considered an extension of the Efimov plot for three bosons to the case of three $1/2$-spin-isospin fermions.
Weakly bound states with spin-isospin symmetry
Directory of Open Access Journals (Sweden)
Kievsky A.
2016-01-01
Full Text Available We discuss weakly bound states of a few-fermion system having spin-isospin symmetry. This corresponds to the nuclear physics case in which the singlet, a0, and triplet, a1, n − p scattering lengths are large with respect to the range of the nuclear interaction. The ratio of the two is about a0/a1 ≈ −4.31. This value defines a plane in which a0 and a1 can be varied up to the unitary limit, 1/a0 = 0 and 1/a1 = 0, maintaining its ratio fixed. Using a spin dependant potential model we estimate the three-nucleon binding energy along that plane. This analysis can be considered an extension of the Efimov plot for three bosons to the case of three 1/2-spin-isospin fermions.
Baryons as relativistic three-quark bound states
Eichmann, Gernot; Williams, Richard; Alkofer, Reinhard; Fischer, Christian S
2016-01-01
We review the spectrum and electromagnetic properties of baryons described as relativistic three-quark bound states within QCD. The composite nature of baryons results in a rich excitation spectrum, whilst leading to highly non-trivial structural properties explored by the coupling to external (electromagnetic and other) currents. Both present many unsolved problems despite decades of experimental and theoretical research. We discuss the progress in these fields from a theoretical perspective, focusing on nonperturbative QCD as encoded in the functional approach via Dyson-Schwinger and Bethe-Salpeter equations. We give a systematic overview as to how results are obtained in this framework and explain technical connections to lattice QCD. We also discuss the mutual relations to the quark model, which still serves as a reference to distinguish 'expected' from 'unexpected' physics. We confront recent results on the spectrum of non-strange and strange baryons, their form factors and the issues of two-photon proce...
Rapid thermal co-annihilation through bound states
Kim, Seyong
2016-01-01
The co-annihilation rate of heavy particles close to thermal equilibrium, which plays a role in many classic dark matter scenarios, can be "simulated" in QCD by considering the pair annihilation rate of a heavy quark and antiquark at a temperature of a few hundred MeV. We show that the so-called Sommerfeld factors, parameterizing the rate, can be defined and measured non-perturbatively within the NRQCD framework. Lattice measurements indicate a modest suppression in the octet channel, in reasonable agreement with perturbation theory, and a large enhancement in the singlet channel, much above the perturbative prediction. We suggest that the additional enhancement originates from bound state formation and subsequent decay, omitted in previous estimates of thermal Sommerfeld factors, which were based on Boltzmann equations governing single-particle phase space distributions.
Three-boson bound states in finite volume with EFT
Kreuzer, S.; Hammer, H.-W.
2010-04-01
The universal properties of a three-boson system with large scattering length are well understood within the framework of Effective Field Theory. They include a geometric spectrum of shallow three-body bound states called “Efimov states” and log-periodic dependence of scattering observables on the scattering length. We investigate the modification of this spectrum in a finite cubic box using a partial wave expansion. The dependence of the binding energies on the box size is calculated for systems with positive and negative two-body scattering length. We compare the full results to results obtained using an expansion around the infinite volume binding energy. The renormalization of the Effective Field Theory in the finite volume is verified explicitly.
Bound states in the continuum in open acoustic resonators
Lyapina, A A; Pilipchuk, A S; Sadreev, A F
2015-01-01
We consider bound states in the continuum (BSC) or embedded trapped modes in two- and three-dimensional acoustic axisymmetric duct-cavity structures. We demonstrate numerically that under variation of the length of the cavity multiple BSCs occur due to the Friedrich-Wintgen two-mode full destructive interference mechanism. The BSCs are detected by tracing the resonant widths to the points of the collapse of Fano resonances where one of the two resonant modes acquires infinite life-time. It is shown that the approach of the acoustic coupled mode theory cast in the truncated form of a two-mode approximation allows us to analytically predict the BSC frequencies and shape functions to a good accuracy in both two and three dimensions.
Tunable magnetic textures: From Majorana bound states to braiding
Matos-Abiague, Alex; Shabani, Javad; Kent, Andrew D.; Fatin, Geoffrey L.; Scharf, Benedikt; Žutić, Igor
2017-08-01
A versatile control of magnetic systems, widely used to store information, can also enable manipulating Majorana bounds states (MBS) and implementing fault-tolerant quantum information processing. The proposed platform relies on the proximity-induced superconductivity in a two-dimensional electron gas placed next to an array of magnetic tunnel junctions (MTJs). A change in the magnetization configuration in the MTJ array creates tunable magnetic textures thereby removing several typical requirements for MBS: strong spin-orbit coupling, applied magnetic field, and confinement by one-dimensional structures which complicates demonstrating non-Abelian statistics through braiding. Recent advances in fabricating two-dimensional epitaxial superconductor/semiconductor heterostructures and designing tunable magnetic textures support the feasibility of this novel platform for MBS.
Low-lying quasibound rovibrational states of H2 16O**
Szidarovszky, Tamás; Császár, Attila G.
2013-08-01
A complex coordinate scaling (CCS) method is described allowing the quantum chemical computation of quasibound (also called resonance or metastable) rovibrational states of strongly bound triatomic molecules. The molecule chosen to test the method is H2 16O, for which an accurate global potential energy surface, a previous computation of a few resonance states via the complex absorbing potential (CAP) method, and some Feshbach (J = 0, where J is the quantum number characterising overall rotations of the molecule) and shape (J ≠ 0) resonances measured via a state-selective, triple-resonance technique are all available. Characterisation of the computed resonance states is performed via probability density plots based on CCS rovibrational wavefunctions. Such plots provide useful details about the physical nature of the resonance states. Based on the computations and the resonance plots, the following useful facts about the resonance states investigated are obtained: (a) Feshbach resonances are formed by accumulation of a large amount of energy in either the non-dissociative bending or symmetric streching modes, excitations by more than five quanta are not uncommon; (b) there are several resonance states with low and medium bending excitation, the latter are different from the states observed somewhat below dissociation by the same triple-resonance technique; (c) several types of dissociation bahavior can be identified, varying greatly among the states; (d) several pairs of J = 0 and J = 1 Feshbach resonance states can be identified which differ by rigid-rotor type energies; and (e) the lifetimes of the assigned J = 1 rovibrational Feshbach resonances are considerably longer than the lifetimes of their J = 0 vibrational counterparts.
Probing the Dark Sector with Dark Matter Bound States.
An, Haipeng; Echenard, Bertrand; Pospelov, Maxim; Zhang, Yue
2016-04-15
A model of the dark sector where O(few GeV) mass dark matter particles χ couple to a lighter dark force mediator V, m_{V}≪m_{χ}, is motivated by the recently discovered mismatch between simulated and observed shapes of galactic halos. Such models, in general, provide a challenge for direct detection efforts and collider searches. We show that for a large range of coupling constants and masses, the production and decay of the bound states of χ, such as 0^{-+} and 1^{--} states, η_{D} and ϒ_{D}, is an important search channel. We show that e^{+}e^{-}→η_{D}+V or ϒ_{D}+γ production at B factories for α_{D}>0.1 is sufficiently strong to result in multiple pairs of charged leptons and pions via η_{D}→2V→2(l^{+}l^{-}) and ϒ_{D}→3V→3(l^{+}l^{-}) (l=e,μ,π). The absence of such final states in the existing searches performed at BABAR and Belle sets new constraints on the parameter space of the model. We also show that a search for multiple bremsstrahlung of dark force mediators, e^{+}e^{-}→χχ[over ¯]+nV, resulting in missing energy and multiple leptons, will further improve the sensitivity to self-interacting dark matter.
Potential energy curves for the ground and low-lying excited states of CuAg
Energy Technology Data Exchange (ETDEWEB)
Alizadeh, Davood; Shayesteh, Alireza, E-mail: jamshidi@ccerci.ac.ir, E-mail: ashayesteh@ut.ac.ir [School of Chemistry, College of Science, University of Tehran, 14176 Tehran (Iran, Islamic Republic of); Jamshidi, Zahra, E-mail: jamshidi@ccerci.ac.ir, E-mail: ashayesteh@ut.ac.ir [Chemistry and Chemical Engineering Research Center of Iran, 14335-186 Tehran (Iran, Islamic Republic of)
2014-10-21
The ground and low-lying excited states of heteronuclear diatomic CuAg are examined by multi-reference configuration interaction (MRCI) method. Relativistic effects were treated and probed in two steps. Scalar terms were considered using the spin-free DKH Hamiltonian as a priori and spin-orbit coupling was calculated perturbatively via the spin-orbit terms of the Breit-Pauli Hamiltonian based on MRCI wavefunctions. Potential energy curves of the spin-free states and their corresponding Ω components correlating with the separated atom limits {sup 2}S(Cu) + {sup 2}S(Ag) and {sup 2}D(Cu) + {sup 2}S(Ag) are obtained. The results are in fine agreement with the experimental measurements and tentative conclusions for the ion-pair B0{sup +} state are confirmed by our theoretical calculations. Illustrative results are presented to reveal the relative importance and magnitude of the scalar and spin-orbit effects on the spectroscopic properties of this molecule. Time dependent density functional theory calculations, using the LDA, BLYP, B3LYP, and SAOP functionals have been carried out for CuAg and the accuracy of TD-DFT has been compared with ab initio results.
Bounds for entanglement of formation of two mode squeezed thermal states
Chen, X Y; Chen, Xiao-Yu; Qiu, Pei-liang
2003-01-01
The upper and lower bounds of entanglement of formation are given for two mode squeezed thermal state. The bounds are compared with other entanglement measure or bounds. The entanglement distillation and the relative entropy of entanglement of infinitive squeezed state are obtained at the postulation of hashing inequality.
Two-vibron bound states in the β-Fermi-Pasta-Ulam model
Institute of Scientific and Technical Information of China (English)
Hu Xin-Guang; Tang Yi
2008-01-01
This paper studies the two-vibron bound states in the β-Fermi-Pasta-Ulam model by means of the number conserving approximation combined with the number state method.The results indicate that on-site,adjacent-site and mixed two-vibron bound states may exist in the model.Specially,wave number has a significant effect on such bound states,which may be considered as the quantum effects of the localized states in quantum systems.
Probing ground and low-lying excited states for HIO{sub 2} isomers
Energy Technology Data Exchange (ETDEWEB)
Souza, Gabriel L. C. de [Departamento de Química, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso 78060-900 (Brazil); Instituto de Ciências Exatas e Tecnologia, Universidade Federal do Amazonas, Itacoatiara, Amazonas 69100-000 (Brazil); Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2 (Canada); Brown, Alex, E-mail: alex.brown@ualberta.ca [Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2 (Canada)
2014-12-21
We present a computational study on HIO{sub 2} molecules. Ground state properties such as equilibrium structures, relative energetics, vibrational frequencies, and infrared intensities were obtained for all the isomers at the coupled-cluster with single and double excitations as well as perturbative inclusion of triples (CCSD(T)) level of theory with the aug-cc-pVTZ-PP basis set and ECP-28-PP effective core potential for iodine and the aug-cc-pVTZ basis set for hydrogen and oxygen atoms. The HOIO structure is confirmed as the lowest energy isomer. The relative energies are shown to be HOIO < HOOI < HI(O)O. The HO(O)I isomer is only stable at the density functional theory (DFT) level of theory. The transition states determined show interconversion of the isomers is possible. In order to facilitate future experimental identification, vibrational frequencies are also determined for all corresponding deuterated species. Vertical excitation energies for the three lowest-lying singlet and triplet excited states were determined using the configuration interaction singles, time-dependent density functional theory (TD-DFT)/B3LYP, TD-DFT/G96PW91, and equation of motion-CCSD approaches with the LANL2DZ basis set plus effective core potential for iodine and the aug-cc-pVTZ basis set for hydrogen and oxygen atoms. It is shown that HOIO and HOOI isomers have excited states accessible at solar wavelengths (<4.0 eV) but these states have very small oscillator strengths (<2 × 10{sup −3})
Probing ground and low-lying excited states for HIO2 isomers
de Souza, Gabriel L. C.; Brown, Alex
2014-12-01
We present a computational study on HIO2 molecules. Ground state properties such as equilibrium structures, relative energetics, vibrational frequencies, and infrared intensities were obtained for all the isomers at the coupled-cluster with single and double excitations as well as perturbative inclusion of triples (CCSD(T)) level of theory with the aug-cc-pVTZ-PP basis set and ECP-28-PP effective core potential for iodine and the aug-cc-pVTZ basis set for hydrogen and oxygen atoms. The HOIO structure is confirmed as the lowest energy isomer. The relative energies are shown to be HOIO < HOOI < HI(O)O. The HO(O)I isomer is only stable at the density functional theory (DFT) level of theory. The transition states determined show interconversion of the isomers is possible. In order to facilitate future experimental identification, vibrational frequencies are also determined for all corresponding deuterated species. Vertical excitation energies for the three lowest-lying singlet and triplet excited states were determined using the configuration interaction singles, time-dependent density functional theory (TD-DFT)/B3LYP, TD-DFT/G96PW91, and equation of motion-CCSD approaches with the LANL2DZ basis set plus effective core potential for iodine and the aug-cc-pVTZ basis set for hydrogen and oxygen atoms. It is shown that HOIO and HOOI isomers have excited states accessible at solar wavelengths (<4.0 eV) but these states have very small oscillator strengths (<2 × 10-3).
Dirac Coupled Channel Analyses of the high-lying excited states at $^{22}$Ne(p,p$'$)$^{22}$Ne
Shim, Sugie
2015-01-01
Dirac phenomenological coupled channel analyses are performed using an optical potential model for the high-lying excited vibrational states at 800 MeV unpolarized proton inelastic scatterings from $^{22}$Ne nucleus. Lorentz-covariant scalar and time-like vector potentials are used as direct optical potentials and the first-order vibrational collective model is used for the transition optical potentials to describe the high-lying excited vibrational collective states. The complicated Dirac coupled channel equations are solved phenomenologically using a sequential iteration method by varying the optical potential and the deformation parameters. Relativistic Dirac coupled channel calculations are able to describe the high-lying excited states of the vibrational bands in $^{22}$Ne clearly better than the nonrelativistic coupled channel calculations. The channel-coupling effects of the multistep process for the excited states of the vibrational bands are investigated. The deformation parameters obtained from the ...
DEFF Research Database (Denmark)
Shim, Irene; Gingerich, K. A.
2000-01-01
The three lowest-lying electronic states of RuC, (1)Sigma(+), (3)Delta, and (1)Delta, have been investigated by performing all-electron ab initio multi-configuration self-consistent-field (CASSCF) and multi-reference configuration interaction (MRCI) calculations including relativistic corrections....... The electronic ground state is derived as (1)Sigma(+) with the spectroscopic constants r(e) = 1.616 Angstrom and omega(e) = 1085 cm(-1). The lowest-lying excited state, (3)Delta, has r(e) = 1.632 Angstrom, omega(e) = 1063 cm(-1), and T-e = 912 cm(-1). These results are consistent with recent spectroscopic values....... The chemical bonds in all three lowest-lying states are triple bonds composed of one sigma and two pi bonds. (C) 2000 Elsevier Science B.V. All rights reserved....
Theoretical spectroscopic constants for the low-lying states of the oxides and sulfides of Mo and Tc
Langhoff, Stephen R.; Bauschlicher, Charles W., Jr.; Pettersson, Lars G. M.; Siegbahn, Per E. M.
1989-01-01
Spectroscopic results were determined for the ground and low-lying states of the oxides and sulfides of Mo and Tc, using the single-reference-based modified coupled pair functional method of Ahlrichs et al. (1985) and Chong et al. (1986) and the multireference-based state-averaged CASSCF/MRCI method. Spectroscopic constants, dipole moments, Mulliken populations, and radiative lifetimes were calculated for selected low-lying states of these molecular systems. The spectroscopy of the MoS and TcS molecules was found to be quite analogous to the corresponding oxides.
Bound state spectra of the 3D rational potential
Roy, Amlan K; Proynov, Emil I
2010-01-01
We present bound state spectra of the 3D rational potential, $V(r)=r^2 + \\lambda r^2/(1+gr^2)$, $g>0$, by means of the generalized pseudospectral method. All the thirty states corresponding to $n$=0--9 are considered for the first time for a broad range of coupling parameters. These results surpass the accuracy of \\emph{all} other existing calculations published so far except the finite-difference method, which yields similar accuracy as ours. Variation of energies and radial distribution functions is followed with respect to the interaction parameters. Special emphasis has been laid on \\emph{higher} excitations and \\emph{negative} values of the interaction, where relatively less work has been reported. The energy sequence is found to be different for positive and negative interaction; numerically following a mirror-image relationship \\emph{usually}, if not always. Additionally, twenty energy splittings arising from certain levels belonging to $n$=0--9 are systematically studied as functions of the potential ...
Jafarizadeh, M. A.; Majarshin, A. Jalili; Fouladi, N.
2016-11-01
In order to investigate negative parity states, it is necessary to consider negative parity-bosons additionally to the usual s- and d-bosons. The dipole and octupole degrees of freedom are essential to describe the observed low-lying collective states with negative parity. An extended interacting boson model (IBM) that describes pairing interactions among s, p, d and f-boson based on affine SU(1, 1) Lie algebra in the quantum phase transition (QPT) field, such as spd-IBM, sdf-IBM and spdf-IBM, is composed based on algebraic structure. In this paper, a solvable extended transitional Hamiltonian based on affine SU(1, 1) Lie algebra is proposed to describe low-lying positive and negative parity states between the spherical and deformed gamma-unstable shape. Three model of new algebraic solution for even-even nuclei are introduced. Numerical extraction to low-lying energy levels and transition rates within the control parameters of this evaluated Hamiltonian are presented for various N values. We reproduced the positive and negative parity states and our calculations suggest that the results of spdf-IBM are better than spd-IBM and sdf-IBM in this literature. By reproducing the experimental results, the method based on signature of the phase transition such as level crossing in the lowest excited states is used to provide a better description of Ru isotopes in this transitional region.
Theoretical calculation of low-lying states of NaAr and NaXe
Laskowski, B. C.; Langhoff, S. R.; Stallcop, J. R.
1981-01-01
Potential curves as well as dipole moments and linking transition moments are calculated for the ground X 2 Sigma + and low lying excited A 2 Pi, B 2 Sigma +, C 2 Sigma +, (4) 2 Sigma +, (2) 2 Pi and (1) 2 Delta states of NaAr and NaXe. Calculations are performed using a self-consistent field plus configuration-interaction procedure with the core electrons replaced by an ab initio effective core potential. The potential curves obtained are found to be considerably less repulsive than the semiempirical curves of Pascale and Vandeplanque (1974) and to agree well with existing experimental data, although the binding energies of those states having potential minima due to van der Waals interactions are underestimated. Emission bands are also calculated for the X 2 Sigma + - C 2 Sigma + excimer transitions of NaAr and NaXe using the calculated transition moments and potential curves, and shown to agree well with experiment on the short-wavelength side of the maximum.
Dynamics of the higher lying excited states of cyanine dyes. An ultrafast fluorescence study.
Guarin, Cesar A; Villabona-Monsalve, Juan P; López-Arteaga, Rafael; Peon, Jorge
2013-06-20
The electronic relaxation dynamics of the second singlet excited states of several cyanine dyes was studied through the femtosecond fluorescence up-conversion technique. Our interest in these molecules comes from the potential applications of systems with upper excited singlet states with a long lifetime, which can include electron and energy transfer from the higher lying singlets after one- or two-photon absorption. We studied three series of cyanines with 4-quinolyl, 2-quinolyl, or benzothiazolyl type end groups, each with varying sp(2) carbon conjugation lengths in the methinic bridge. The dynamics after electronic excitation to singlet states above the fluorescent state vary significantly as a function of cyanine structure and conjugation length. In particular, for the 4-quinolyl series the cyanine with an intermediate conjugation length (three methinic carbons) has the slowest S2 decays with lifetimes of 5.4 ps in ethanol and 6.6 ps in ethylene glycol. On the other hand, we observed that the 2-quinolyl family has S2 decay times in the subpicosecond range independent of the conjugation length between the end groups. The slowest internal conversion was observed for the benzothiazolyl type cyanine with five methinic carbons, with an S2 lifetime of 17.3 ps in ethanol. For the planar cyanines of this study we observed for the first time a clear systematic trend in the S2 decay times which closely follow the energy gap law. It was also demonstrated that a slow S2 decay is as well observed upon excitation through degenerate two-photon absorption with near-IR pulses. The present study isolates the most important variables for the design of cyanines with long S2 lifetimes.
Theoretical studies of the low-lying states of ScO, ScS, VO, and VS
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.
1986-01-01
Bonding in the low-lying states of ScO, ScS, VO, and VS is theoretically studied. Excellent agreement is obtained with experimental spectroscopic constants for the low-lying states of ScO and VO. The results for VS and ScS show that the bonding in the oxides and sulfides is similar, but that the smaller electronegativity in S leads to a smaller ionic component in the bonding. The computed D0 of the sulfides are about 86 percent of the corresponding oxides, and the low-lying excited states are lower in the sulfides than in the corresponding oxides. The CPF method is shown to be an accurate and cost-effective method for obtaining reliable spectroscopic constants for these systems.
Baryons as relativistic three-quark bound states
Eichmann, Gernot; Sanchis-Alepuz, Hèlios; Williams, Richard; Alkofer, Reinhard; Fischer, Christian S.
2016-11-01
We review the spectrum and electromagnetic properties of baryons described as relativistic three-quark bound states within QCD. The composite nature of baryons results in a rich excitation spectrum, whilst leading to highly non-trivial structural properties explored by the coupling to external (electromagnetic and other) currents. Both present many unsolved problems despite decades of experimental and theoretical research. We discuss the progress in these fields from a theoretical perspective, focusing on nonperturbative QCD as encoded in the functional approach via Dyson-Schwinger and Bethe-Salpeter equations. We give a systematic overview as to how results are obtained in this framework and explain technical connections to lattice QCD. We also discuss the mutual relations to the quark model, which still serves as a reference to distinguish 'expected' from 'unexpected' physics. We confront recent results on the spectrum of non-strange and strange baryons, their form factors and the issues of two-photon processes and Compton scattering determined in the Dyson-Schwinger framework with those of lattice QCD and the available experimental data. The general aim is to identify the underlying physical mechanisms behind the plethora of observable phenomena in terms of the underlying quark and gluon degrees of freedom.
Coexistence of bound and virtual-bound states in shallow-core to valence x-ray spectroscopies
Sen Gupta, Subhra; Bradley, J. A.; Haverkort, M. W.; Seidler, G. T.; Tanaka, A.; Sawatzky, G. A.
2011-08-01
With the example of the non-resonant inelastic x-ray scattering (NIXS) at the O45 edges (5d→5f) of the actinides, we develop the theory for shallow-core to valence excitations, where the multiplet spread is larger than the core-hole attraction, such as if the core and valence orbitals have the same principal quantum number. This involves very strong final state configuration interaction (CI), which manifests itself as huge reductions in the Slater-Condon integrals, needed to explain the spectral shapes within a simple renormalized atomic multiplet theory. But more importantly, this results in a cross-over from bound (excitonic) to virtual-bound excited states with increasing energy, within the same core-valance multiplet structure, and in large differences between the dipole and high-order multipole transitions, as observed in NIXS. While the bound states (often higher multipole allowed) can still be modeled using local cluster-like models, the virtual-bound resonances (often dipole-allowed) cannot be interpreted within such local approaches. This is in stark contrast to the more familiar core-valence transitions between different principal quantum number shells, where all the final excited states almost invariably form bound core-hole excitons and can be modeled using local approaches. The possibility of observing giant multipole resonances for systems with high angular momentum ground states is also predicted. The theory is important to obtain ground state information from core-level x-ray spectroscopies of strongly correlated transition metal, rare-earth, and actinide systems.
On the low-lying states of WO - A comparison with CrO and MoO
Nelin, C. J.; Bauschlicher, C. W., Jr.
1985-01-01
The four low-lying states of WO were investigated and compared with similar states of CrO and MoO. For all these systems the ground state is 5 Pi, but the ordering of the upper states is different between WO and either CrO or MoO. The difference in the state ordering arises in part from the fact that in WO all of the states are formed from W(+) in a d4S1 configuration, whereas in both CrO and MoO some states are formed from the d5 configuration and others from the d4S1 configuration.
Role of 'quasiparticle x phonon' components in gamma-decay of high-lying states
Energy Technology Data Exchange (ETDEWEB)
Ponomarev, V.Yu.; Soloviev, V.G.; Vdovin, A.I.; Stoyanov, C.
1987-01-15
The ..gamma.. decay rates of highly excited nuclear states of odd-mass nuclei into the low-lying one-quasiparticle states are calculated in a microscopic way. We conclude that not only the one quasiparticle component but also ''quasiparticle x phonon'' components of the wave function of highly excited states can play an important role in their ..gamma.. decay.
Bound states and critical behavior of the Yukawa potential
Institute of Scientific and Technical Information of China (English)
LI; Yongyao
2006-01-01
[1]Yukawa,H.,On the interaction of elementary particles,Proc.Phys.Math Soc.Jap.,1935,17:48-57.[2]Sachs,R.,Goeppert-Mayer,M.,Calculations on a new neutron-proton interaction potential,Phys.Rev.,1938,53:991-993.[3]Harris,G.,Attractive two-body interactions in partially ionized plasmas,Phys.Rev.,1962,125:1131-1140.[4]Schey,H.,Schwartz,J.,Counting the bound states in short-range central potentials,Phys.Rev.B,1965,139:1428-1432.[5]Rogers,J.,Graboske,H.,Harwood,E.,Bound eigenstates of the static screened Coulomb poten-tial,Phys.Rev.A,1970,1:1577-1586.[6]McEnnan,J.,Kissel,L.,Pratt,R.,Analytic perturbation theory for screened Coulomb potentials:non-relativistic case,Phys.Rev.A,1976,13:532-559.[7]Gerry,C.,Estimates of the ground states of the Yukawa potential from the Bogoliubov inequality,J.Phys.A,1984,17:L313-L315.[8]Kr(o)ger,H.,Girard,R.,Dufour,G.,Direct calculation of the S matrix in coordinate space,Phys.Rev.C,1988,37:486-496.[9]Girard,R.,Kr(o)ger,H.,Labelle,P.et al.,Computation of a long time evolution in a Schr(o)dinger system,Phys.Rev.A,1988,37:3195-3200.[10]Garavelli,S.,Oliveira,F.,Analytical solution for a Yukawa-type potential,Phys.Rev.Lett.,1991,66:1310-1313.[11]Gomes,O.,Chacham,H.,Mohallem,J.,Variational calculations for the bound-unbound transition of the Yukawa potential,Phys.Rev.A,1994,50:228-231.[12]Yukalov,V.,Yukalova,E.,Oliveira,F.,Renormalization-group solutions for Yukawa potential,J.Phys.A,1998,31:4337-4348.[13]Brau,F.,Necessary and sufficient conditions for existence of bound states in a central potential,J.Phys.A,2003,36:9907-9913.[14]Bertini,L.,Mella,M.,Bressanini,D.et al.,Borromean binding in H-2 with Yukawa potential:a nonadiabatic quantum Monte Carlo study,Phys.Rev.A,2004,69:042504.[15]Dean,D.,Drummond,I.,Horgan,R.,Effective diffusion constant in a two-dimensional medium of charged point scatterers,J.Phys.A,2004,37:2039-2046.[16]De-Leo,S.,Rotelli,P.,Amplification of coupling for Yukawa potentials,Phys.Rev.D,2004,69:034006.[17]Khrapak
Variational Mass Perturbation Theory for Light-Front Bound-State Equations
Harada, K; Stern, C; Harada, Koji; Heinzl, Thomas; Stern, Christian
1998-01-01
We investigate the mesonic light-front bound-state equations of the 't Hooft and Schwinger model in the two-particle, i.e. valence sector, for small fermion mass. We perform a high precision determination of the mass and light-cone wave function of the lowest lying meson by combining fermion mass perturbation theory with a variational approach. All calculations are done entirely in the fermionic representation without using any bosonization scheme. In a step-by-step procedure we enlarge the space of variational parameters. For the first two steps, the results are obtained analytically. Beyond that we use computer algebraic and numerical methods. We achieve good convergence so that the calculation of the meson mass squared can be extended to third order in the fermion mass. Within the numerical treatment we include higher Fock states up to six particles. Our results are consistent with all previous numerical investigations, in particular lattice calculations. For the massive Schwinger model, we find a small di...
String Models for the Heavy Quark-Antiquark Bound States.
Tse, Sze-Man
1988-12-01
The heavy quark-antiquark bound state is examined in the phenomenological string models. Specifically, the Nambu-Goto model and the Polyakov's smooth string model are studied in the large-D limit, D being the number of transverse space-time dimensions. The static potential V(R) is extracted in both models in the large-D limit. In the former case, this amounts to the usual saddle point calculation. In the latter case, the renormalized, physical string tension is expressed in terms of the bare string tension and the extrinsic curvature coupling. A systematic loop expansion of V(R) is developed and carried out explicitly to one loop order, with the two loops result presented without detail. For large separations R, the potential is linear in R with corrections of order 1/R. The coefficient of the 1/R Luscher term has the universal value -piD/24 to any finite order in the loop expansion. For very small separations R, the potential V(R) is also proportional to 1/R with a coefficient twice that of Luscher's term. The corrections are logarithmically small. Polyakov's smooth string model is extended to the finite temperature situation. The temperature dependence of the string tension is investigated in the large-D limit. The effective string tension is calculated to the second order in the loop expansion. At low temperature, it differs from that of the Nambu-Goto model only by terms that fall exponentially with inverse temperature. Comparison of the potential V(R) in the smooth string model with lattice gauge calculation and hadron spectroscopy data yields a consistent result.
Theoretical study of the low-lying electronic states of ZnO and ZnS
Bauschlicher, C. W., Jr.; Langhoff, S. R.
1986-01-01
Theoretical spectroscopic constants and dipole moments are determined for the 1 Sigma(+), 1,3 Pi, and 3 Sigma(+) states of ZnO and ZnS, using extended Gaussian basis sets and incorporating correlation using both configuration-interaction and coupled pair (CPF) methods. Relativistic corrections (Darwin plus mass velocity), included using first-order perturbation theory, are relatively small. At the CPF level, both ZnO and ZnS have 1 Sigma(+) ground states, with the 3 Pi state lying 209 and 2075/cm higher, respectively. The 3 Sigma(+) state lies about 1.5 eV higher in ZnO and 2.1 eV higher in ZnS. The 1,3 Pi states are relatively close together since the exchange splitting is small with the sigma electron localized on Zn and the pi electron on oxygen (or sulfur).
Heyman, Gail D.; Luu, Diem H.; Lee, Kang
2009-01-01
The present set of studies identifies the phenomenon of "parenting by lying", in which parents lie to their children as a means of influencing their emotional states and behaviour. In Study 1, undergraduates (n = 127) reported that their parents had lied to them while maintaining a concurrent emphasis on the importance of honesty. In Study 2 (n =…
Low-lying T=0 states in the odd–odd N=Z nucleus {sup 62}Ga
Energy Technology Data Exchange (ETDEWEB)
David, H.M., E-mail: hdavid@anl.gov [University of Edinburgh, Edinburgh, EH9 3JZ (United Kingdom); Woods, P.J.; Lotay, G. [University of Edinburgh, Edinburgh, EH9 3JZ (United Kingdom); Seweryniak, D.; Albers, M.; Alcorta, M.; Carpenter, M.P. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Chiara, C.J. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); University of Maryland, College Park, MD 20742 (United States); Davinson, T.; Doherty, D.T. [University of Edinburgh, Edinburgh, EH9 3JZ (United Kingdom); Hoffman, C.R.; Janssens, R.V.F.; Lauritsen, T.; Rogers, A.M.; Zhu, S. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)
2013-11-04
New, low-lying levels in the odd–odd, N=Z nucleus {sup 62}Ga have been identified using a sensitive technique, where in-beam γ rays from short-lived nuclei are tagged with β decays following recoil mass identification. A comparison of the results with shell-model and IBM-4 calculations demonstrates good agreement between theory and experiment, with the majority of predicted low-lying, low-spin T=0 states now identified. There is a dramatic change in the level density at low excitation energies for the N=Z nucleus {sup 62}Ga when compared with neighbouring odd–odd Ga isotopes where, in contrast, the low-lying level structure is dominated by configurations with T=1 pairing interactions between excess neutrons. This illustrates the distinctively different aspects of nuclear structure exhibited by nuclei with N=Z.
Bound states for fermions in the gauge Aharonov-Bohm field
Energy Technology Data Exchange (ETDEWEB)
Voropaev, S.A.; Galtsov, D.V.; Spasov, D.A. (Dept. of Theoretical Physics, Moscow State Univ. (USSR))
1991-09-05
In this paper we discuss some interesting properties of the Aharonov-Bohm interaction for relativistic spin-one-half particles. We will show that the AB potential is powerful enough to create bound states. We will then discuss the wave function, spin-coefficients and the energy level for the bound states of the fermions in the gauge AB field. (orig.).
The bound state S-matrix for AdS5×S5 superstring
Arutyunov, G.E.; de Leeuw, M.; Torrielli, A.
2009-01-01
We determine the S-matrix that describes scattering of arbitrary bound states in the light-cone string theory in AdS5×S5. The corresponding construction relies on the Yangian symmetry and the superspace formalism for the bound state representations. The basic analytic structure supporting the S-matr
Trilinear couplings and scalar bound states in supersymmetric extensions of the standard model
Hernández, Pilar; Sanz, V
2001-01-01
The trilinear terms in minimal supersymmetric extensions of the standard model can be responsible of forming a bound state of scalars. In this talk we outline our results on the study of this bound state using a non-perturbative method, the exact renormalization group. We focus on the trilinear term between the Higgs and stop fields. (4 refs).
The Bethe ansatz for AdS5 × S5 bound states
de Leeuw, M.
2009-01-01
We reformulate the nested coordinate Bethe ansatz in terms of coproducts of Yangian symmetry generators. This allows us to derive the nested Bethe equations for arbitrary bound state string S-matrices. The bound state number dependence in the Bethe equations appears through the parameters x± and the
Improved lower bounds on the ground-state entropy of the antiferromagnetic Potts model.
Chang, Shu-Chiuan; Shrock, Robert
2015-05-01
We present generalized methods for calculating lower bounds on the ground-state entropy per site, S(0), or equivalently, the ground-state degeneracy per site, W=e(S(0)/k(B)), of the antiferromagnetic Potts model. We use these methods to derive improved lower bounds on W for several lattices.
Ensemble-based characterization of unbound and bound states on protein energy landscape
Ruvinsky, Anatoly M; Tuzikov, Alexander V; Vakser, Ilya A
2012-01-01
Characterization of protein energy landscape and conformational ensembles is important for understanding mechanisms of protein folding and function. We studied ensembles of bound and unbound conformations of six proteins to explore their binding mechanisms and characterize the energy landscapes in implicit solvent. First, results show that bound and unbound spectra often significantly overlap. Moreover, the larger the overlap the smaller the RMSD between bound and unbound conformational ensembles. Second, the analysis of the unbound-to-bound changes points to conformational selection as the binding mechanism for four of the proteins. Third, the center of the unbound spectrum has a higher energy than the center of the corresponding bound spectrum of the dimeric and multimeric states for most of the proteins. This suggests that the unbound states often have larger entropy than the bound states considered outside of the complex. Fourth, the exhaustively long minimization, making small intra-rotamer adjustments, ...
Low-lying isomeric state in {sup 80}Ga from the {beta}{sup -} decay of {sup 80}Zn
Energy Technology Data Exchange (ETDEWEB)
LicA, R.; Marginean, N.; Ghita, D.G. [Horia Hulubei National Institute for Physics and Nuclear Engineering, Bucharest (Romania); and others
2012-10-20
A new level scheme was constructed for {sup 80}Ga which is significantly different from the one previously reported. The excitation energy of a new low-lying state recently reported in [2] was identified at 22.4 keV. Properties of the level scheme suggest that the ground state has spin J = 6 and the first excited state has spin J = 3. The spin assignments are in agreement with laser spectroscopy values previously measured. Our work provides the first evidence for the J = 6 being the ground state.
Ab initio multi-reference configuration interaction of the low-lying states of the AsP molecule
Institute of Scientific and Technical Information of China (English)
Ling Zhang; Chuanlu Yang; Tingqi Ren; Meishan Wang
2008-01-01
Nine low-lying electronic states of the AsP molecule, including Σ+, Ⅱ, and △ symmetries with singlet, triplet, and quintet spin multiplicities, are studied using multi-reference configuration interaction method.The potential energy curves and the spectroscopic constants of these nine states are determined, and compared with the experimental observed data as well as other theoretical works available at present.Three quintet states are reported for the first time.Furthermore, the analytical potential energy functions of these states are fitted using Murrell-Sorbie function and least square fitting method.
Jacobson, Nathan
1979-01-01
Lie group theory, developed by M. Sophus Lie in the 19th century, ranks among the more important developments in modern mathematics. Lie algebras comprise a significant part of Lie group theory and are being actively studied today. This book, by Professor Nathan Jacobson of Yale, is the definitive treatment of the subject and can be used as a textbook for graduate courses.Chapter I introduces basic concepts that are necessary for an understanding of structure theory, while the following three chapters present the theory itself: solvable and nilpotent Lie algebras, Carlan's criterion and its
Formation of bound states in expanded metal studied via path integral molecular dynamics
Deymier, P. A.; Oh, Ki-Dong
2004-03-01
The usefulness of the restricted path integral molecular dynamics method for the study of strongly correlated electrons is demonstrated by studying the formation of bound electronic states in a half-filled expanded three-dimensional hydrogenoid body-centred cubic lattice at finite temperature. Starting from a metallic state with one-component plasma character, we find that bound electrons form upon expansion of the lattice. The bound electrons are spatially localized with their centre for the motion of gyration located at ionic positions. The number of bound electrons increases monotonically with decreasing density.
Interacting quantum walkers: two-body bosonic and fermionic bound states
Krapivsky, P. L.; Luck, J. M.; Mallick, K.
2015-11-01
We investigate the dynamics of bound states of two interacting particles, either bosons or fermions, performing a continuous-time quantum walk on a one-dimensional lattice. We consider the situation where the distance between both particles has a hard bound, and the richer situation where the particles are bound by a smooth confining potential. The main emphasis is on the velocity characterizing the ballistic spreading of these bound states, and on the structure of the asymptotic distribution profile of their center-of-mass coordinate. The latter profile generically exhibits many internal fronts.
Quasi-bound states, resonance tunnelling, and tunnelling times generated by twin symmetric barriers
Indian Academy of Sciences (India)
A Uma Maheswari; P Prema; S Mahadevan; C S Shastry
2009-12-01
In analogy with the definition of resonant or quasi-bound states used in three-dimensional quantal scattering, we define the quasi-bound states that occur in one-dimensional transmission generated by twin symmetric potential barriers and evaluate their energies and widths using two typical examples: (i) twin rectangular barrier and (ii) twin Gaussian-type barrier. The energies at which reflectionless transmission occurs correspond to these states and the widths of the transmission peaks are also the same as those of quasi-bound states. We compare the behaviour of the magnitude of wave functions of quasi-bound states with those for bound states and with the above-barrier state wave function. We deduce a Breit–Wigner-type resonance formula which neatly describes the variation of transmission coefficient as a function of energy at below-barrier energies. Similar formula with additional empirical term explains approximately the peaks of transmission coefficients at above-barrier energies as well. Further, we study the variation of tunnelling time as a function of energy and compare the same with transmission, reflection time and Breit–Wigner delay time around a quasi-bound state energy. We also find that tunnelling time is of the same order of magnitude as lifetime of the quasi-bound state, but somewhat larger.
Energy Technology Data Exchange (ETDEWEB)
Karmakar, Shreetama; Mukhopadhyay, Deb Pratim; Chakraborty, Tapas, E-mail: pctc@iacs.res.in [Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India)
2015-05-14
Multiple fluorine atom substitution effect on photophysics of an aromatic chromophore has been investigated using phenol as the reference system. It has been noticed that the discrete vibronic structure of the S{sub 1}←S{sub 0} absorption system of phenol vapor is completely washed out for pentafluorophenol (PFP), and the latter also shows very large Stokes shift in the fluorescence spectrum. For excitations beyond S{sub 1} origin, the emission yield of PFP is reduced sharply with increase in excess vibronic energy. However, in a collisional environment like liquid hydrocarbon, the underlying dynamical process that drives the non-radiative decay is hindered drastically. Electronic structure theory predicts a number of low-lying dark electronic states of πσ{sup ∗} character in the vicinity of the lowest valence ππ{sup ∗} state of this molecule. Tentatively, we have attributed the excitation energy dependent non-radiative decay of the molecule observed only in the gas phase to an interplay between the lowest ππ{sup ∗} and a nearby dissociative πσ{sup ∗} state. Measurements in different liquids reveal that some of the dark excited states light up with appreciable intensity only in protic liquids like methanol and water due to hydrogen bonding between solute and solvents. Electronic structure theory methods indeed predict that for PFP-(H{sub 2}O){sub n} clusters (n = 1-11), intensities of a number of πσ{sup ∗} states are enhanced with increase in cluster size. In contrast with emitting behavior of the molecule in the gas phase and solutions of nonpolar and polar aprotic liquids, the fluorescence is completely switched off in polar protic liquids. This behavior is a chemically significant manifestation of perfluoro effect, because a very opposite effect occurs in the case of unsubstituted phenol for which fluorescence yield undergoes a very large enhancement in protic liquids. Several dynamical mechanisms have been suggested to interpret the
Institute of Scientific and Technical Information of China (English)
郑雨军; 丁世良
2000-01-01
The vibrational excitations of bent triatomic molecules are studied by using Lie algebra. The RMS error of fitting 30 spectroscopic data is 1.66 cm-1 for SO2. The results show that the expansion of a molecular algebraic Hamiltonian can well describe the experimental data. And the total vibrational levels can be calculated using this Hamiltonian. At the same time, the potential energy surface can also be obtained with the algebraic Hamiltonian.
Langhoff, Stephen R.; Pettersson, Lars G. M.; Bauschlicher, Charles W., Jr.; Partridge, Harry
1987-01-01
A systematic analysis of the low-lying states of all of the second-row transition metal (TM) hydrides except CdH is reported. The calculations included the dominant relativistic contributions through the use of the relativistic effective core potentials of Hay and Wadt (1985). Electron correlation was incorporated, using single-plus-double configuration interaction, the coupled pair functional (CPF) formalism of Ahlrichs et al. (1985), and the Chong and Langhoff (1986) modified version of the CPF method. The spectroscopic parameters D(e), r(e), and mu(e) determined for the low-lying states are compared with the available experimental data and previous theoretical results. In contrast to the first-row TM hydrides studied earlier (Chong et al., 1986), the spectroscopic constants for the second-row TM hydrides were found to be much less sensitive to the level of correlation treatment.
Langhoff, Stephen R.; Pettersson, Lars G. M.; Bauschlicher, Charles W., Jr.; Partridge, Harry
1987-01-01
A systematic analysis of the low-lying states of all of the second-row transition metal (TM) hydrides except CdH is reported. The calculations included the dominant relativistic contributions through the use of the relativistic effective core potentials of Hay and Wadt (1985). Electron correlation was incorporated, using single-plus-double configuration interaction, the coupled pair functional (CPF) formalism of Ahlrichs et al. (1985), and the Chong and Langhoff (1986) modified version of the CPF method. The spectroscopic parameters D(e), r(e), and mu(e) determined for the low-lying states are compared with the available experimental data and previous theoretical results. In contrast to the first-row TM hydrides studied earlier (Chong et al., 1986), the spectroscopic constants for the second-row TM hydrides were found to be much less sensitive to the level of correlation treatment.
Laser-induced fluorescence spectroscopy of jet-cooled TiC: Observation of low-lying 1Σ+ states
Nakhate, S. G.; Mukund, Sheo; Bhattacharyya, Soumen
2017-07-01
The TiC has been investigated using laser-induced fluorescence spectroscopy. The a1Σ+, b1Σ+, and c1Σ+ states are found to lie respectively at T0 = 319.3, 786.0, and 1407.2 cm-1 and have internuclear distances respectively of r0 = 1.6607, 1.6906, and 1.6927 Å. Similar r0 values of the b1Σ+ and c1Σ+ states with that of the X3Σ+ state (1.6953 Å) indicate that either of these states could be isocofigurational to the ground state. Dispersed fluorescence suggests reassignment of the 3Π1 state to a mixed state with dominant 1Π character. Higher spectral resolution of the 1Π-X3Σ+ band provided improved molecular constants.
Bound states of Dipolar Bosons in One-dimensional Systems
DEFF Research Database (Denmark)
G. Volosniev, A.; R. Armstrong, J.; V. Fedorov, D.;
2013-01-01
-body structures in this geometry are determined as function of polarization angles and dipole strength by using both essentially exact stochastic variational methods and the harmonic approximation. The main focus is on the three, four, and five-body problems in two or more tubes. Our results indicate...... that in the weakly-coupled limit the inter-tube interaction is similar to a zero-range term with a suitable rescaled strength. This allows us to address the corresponding many-body physics of the system by constructing a model where bound chains with one molecule in each tube are the effective degrees of freedom...
Photon-assisted tunneling through a topological superconductor with Majorana bound states
Energy Technology Data Exchange (ETDEWEB)
Tang, Han-Zhao; Zhang, Ying-Tao, E-mail: zhangyt@mail.hebtu.edu.cn [College of Physics, Hebei Normal University, Shijiazhuang 050024 (China); Liu, Jian-Jun, E-mail: liujj@mail.hebtu.edu.cn [College of Physics, Hebei Normal University, Shijiazhuang 050024 (China); Department of Physics, Shijiazhuang University, Shijiazhuang 050035 (China)
2015-12-15
Employing the Keldysh Nonequilibrium Green’s function method, we investigate time-dependent transport through a topological superconductor with Majorana bound states in the presence of a high frequency microwave field. It is found that Majorana bound states driven by photon-assisted tunneling can absorb(emit) photons and the resulting photon-assisted tunneling side band peaks can split the Majorana bound state that then appears at non-zero bias. This splitting breaks from the current opinion that Majorana bound states appear only at zero bias and thus provides a new experimental method for detecting Majorana bound states in the Non-zero-energy mode. We not only demonstrate that the photon-assisted tunneling side band peaks are due to Non-zero-energy Majorana bound states, but also that the height of the photon-assisted tunneling side band peaks is related to the intensity of the microwave field. It is further shown that the time-varying conductance induced by the Majorana bound states shows negative values for a certain period of time, which corresponds to a manifestation of the phase coherent time-varying behavior in mesoscopic systems.
Binding Energy of Quantum Bound States in X-shaped Nanowire Intersection
2014-01-01
that with non-zero magnetic field new structures are associated with virtual and resonant states located at the junction that becomes 2D Landau ...results of our model system (cross-wire intersecting at an arbitrary angle) not only supplement the theory of quantum bound state in a classically unbound...geometries has been a long standing problem in quantum theory . Knowledge of quantum bound states in crossed nanowire system is very important in
Becis-Aubry, Yasmina; Boutayeb, Mohamed; Darouach, Mohamed
2006-01-01
International audience; This contribution proposes a recursive and easily implementable online algorithm for state estimation of multi-output discrete-time systems with nonlinear dynamics and linear measurements in presence of unknown but bounded disturbances corrupting both the state and measurement equations. The proposed algorithm is based on state bounding techniques and is decomposed into two steps : time update and observation update that uses a switching estimation Kalman-like gain mat...
On accurate computations of bound state properties in three- and four-electron atomic systems
Frolov, Alexei M
2016-01-01
Results of accurate computations of bound states in three- and four-electron atomic systems are discussed. Bound state properties of the four-electron lithium ion Li$^{-}$ in its ground $2^{2}S-$state are determined from the results of accurate, variational computations. We also consider a closely related problem of accurate numerical evaluation of the half-life of the beryllium-7 isotope. This problem is of paramount importance for modern radiochemistry.
Papi, Paolo; Advances in Lie Superalgebras
2014-01-01
The volume is the outcome of the conference "Lie superalgebras," which was held at the Istituto Nazionale di Alta Matematica, in 2012. The conference gathered many specialists in the subject, and the talks held provided comprehensive insights into the newest trends in research on Lie superalgebras (and related topics like vertex algebras, representation theory and supergeometry). The book contains contributions of many leading esperts in the field and provides a complete account of the newest trends in research on Lie Superalgebras.
Taming the Yukawa potential singularity: improved evaluation of bound states and resonance energies
Alhaidari, A D; Abdelmonem, M S
2007-01-01
Using the tools of the J-matrix method, we absorb the 1/r singularity of the Yukawa potential in the reference Hamiltonian, which is handled analytically. The remaining part, which is bound and regular everywhere, is treated by an efficient numerical scheme in a suitable basis using Gauss quadrature approximation. Analysis of resonance energies and bound states spectrum is performed using the complex scaling method, where we show their trajectories in the complex energy plane and demonstrate the remarkable fact that bound states cross over into resonance states by varying the potential parameters.
Institute of Scientific and Technical Information of China (English)
曹泽星; 吴玮; 张乾二
1997-01-01
Based on the correspondence of the molecular orbital theory and valence bond theory to the description of chemical bonds,the ah imtio valence bond (VB) calculations of the low-lying states of diatomic molecules arc realized.The calculation results for the low-lying states of B2 show that the VB calculation has clear-cut physical significance,and its simulation of the behavior of the potential energy surface about the equilibrium position is superior to that of the molecular orbital theory.The valence bond calculation involving only a few bonded tableaus can correctly re fleet the effect of electronic correlation.
Energy Technology Data Exchange (ETDEWEB)
Hauschild, K.; Bernstein, L.A.; Becker, J.A. [Lawrence Livermore National Lab., CA (United States)] [and others
1996-12-31
The observation of one-step `primary` gamma-ray transitions directly linking the superdeformed (SD) states to the normal deformed (ND) low-lying states of known excitation energies (E{sub x}), spins and parities (J{sup {pi}}) is crucial to determining the E{sub x} and J{sup {pi}} of the SD states. With this knowledge one can begin to address some of the outstanding problems associated with SD nuclei, such as the identical band issue, and one can also place more stringent restrictions on theoretical calculations which predict SD states and their properties. Brinkman, et al., used the early implementation of the GAMMASPHERE spectrometer array (32 detectors) and proposed a single, candidate {gamma} ray linking the {sup 194}Pb yrast SD band to the low-lying ND states in {sup 194}Pb. Using 55 detectors in the GAMMASPHERE array Khoo, et al., observed multiple links between the yrast SD band in {sup 194}Hg and the low-lying level scheme and conclusively determined E{sub x} and J of the yrast SD states. Here the authors report on an experiment in which Gammasphere with 88 detectors was used and the E{sub x} and J{sup {pi}} values of the yrast SD states in {sup 194}Pb were uniquely determined. Twelve one-step linking transitions between the yrast SD band and low-lying states in {sup 194}Pb have been identified, including the transition proposed by Brinkman. These transitions have been placed in the level scheme of {sup 194}Pb using coincidence relationships and agreements between the energies of the primary transitions and the energy differences in level spacings. Furthermore, measurements of angular asymmetries have yielded the multipolarities of the primaries which have allowed J{sup {pi}} assignments of the {sup 194}Pb SD states to be unambiguously determined for the first time without a priori assumptions about the character of SD bands. A study performed in parallel to this work using the EUROGAM-II array reports similar, but somewhat less extensive, results.
Study of the γ decay of high-lying states in 208Pb via inelastic scattering of 17O ions
Directory of Open Access Journals (Sweden)
Crespi F.C.L.
2014-03-01
Full Text Available A measurement of the high-lying states in 208Pb has been made using 17O beams at 20 MeV/u. The gamma decay following inelastic excitation was measured with the detector system AGATA Demonstrator based on segmented HPGe detectors, coupled to an array of large volume LaBr3:Ce scintillators and to an array of Si detectors. Preliminary results in comparison with (γ,γ’ data, for states in the 5-8 MeV energy interval, are presented.
Study of the γ decay of high-lying states in 208Pb via inelastic scattering of 17O ions
Crespi, F. C. L.; Kmiecik, M.; Bracco, A.; Leoni, S.; Maj, A.; Benzoni, G.; Blasi, N.; Boiano, C.; Bottoni, S.; Brambilla, S.; Camera, F.; Ceruti, S.; Giaz, A.; Million, B.; Morales, A. I.; Nicolini, R.; Pellegri, L.; Riboldi, S.; Vandone, V.; Wieland, O.; Bednarczyk, P.; Ciemala, M.; Grebosz, J.; Krzysiek, M.; Mazurek, K.; Zieblinski, M.; Bazzacco, D.; Bellato, M.; Birkenbach, B.; Bortolato, D.; Calore, E.; De Angelis, G.; Farnea, E.; Gadea, A.; Görgen, A.; Gottardo, A.; Isocrate, R.; Lenzi, S.; Lunardi, S.; Mengoni, D.; Michelagnoli, C.; Molini, P.; Napoli, D. R.; Recchia, F.; Sahin, E.; Siebeck, B.; Siem, S.; Ur, C.; Valiente Dobon, J. J.
2014-03-01
A measurement of the high-lying states in 208Pb has been made using 17O beams at 20 MeV/u. The gamma decay following inelastic excitation was measured with the detector system AGATA Demonstrator based on segmented HPGe detectors, coupled to an array of large volume LaBr3:Ce scintillators and to an array of Si detectors. Preliminary results in comparison with (γ,γ') data, for states in the 5-8 MeV energy interval, are presented.
Sp ectroscopy of Low-lying States in Odd-Z Odd-A Nuclei Beyond Lead
Institute of Scientific and Technical Information of China (English)
U Jakobsson; S Juutinen; A Herzan; J Konki; M Leino; M Mallaburn; J Pakarinen; P Papadakis; J Partanen; P Rahkila; M Sandzelius; J Uusitalo; J Saren; C Scholey; J Sorri; S Stolze; K Auranen; H Badran; B Cederwall; D M Cox; T Grahn; P T Greenlees; R Julin
2016-01-01
Low-lying states in odd-Z odd-mass nuclei at the proton drip-line beyond lead have recently been studied through fusion-evaporation reactions using a gas-filled recoil separator. Isomeric 1/2+ and 13/2+ states have been observed in odd-mass astatine and francium nuclei. The systematic behaviour of the level energies of these states have been studied and a similarity between the 1/2+ state in astatine and francium has been found. Furthermore, the 13/2+ state has been observed in the francium nuclei with an oblate behaviour suggesting a coupling of the i13/2 proton to the 2p−2h intruder excitation.
Bicudo, P.; Cardoso, M.
2016-11-01
We address q q Q ¯Q ¯ exotic tetraquark bound states and resonances with a fully unitarized and microscopic quark model. We propose a triple string flip-flop potential, inspired by lattice QCD tetraquark static potentials and flux tubes, combining meson-meson and double Y potentials. Our model includes the color excited potential, but neglects the spin-tensor potentials, as well as all the other relativistic effects. To search for bound states and resonances, we first solve the two-body mesonic problem. Then we develop fully unitary techniques to address the four-body tetraquark problem. We fold the four-body Schrödinger equation with the mesonic wave functions, transforming it into a two-body meson-meson problem with nonlocal potentials. We find bound states for some quark masses, including the one reported in lattice QCD. Moreover, we also find resonances and calculate their masses and widths, by computing the T matrix and finding its pole positions in the complex energy plane, for some quantum numbers. However, a detailed analysis of the quantum numbers where binding exists shows a discrepancy with recent lattice QCD results for the l l b ¯ b ¯ tetraquark bound states. We conclude that the string flip-flop models need further improvement.
Cruising through molecular bound-state manifolds with radiofrequency
Lang, F.; van der Straten, P.; Brandstätter, B.; Thalhammer, G.; Winkler, K.; Julienne, P.S.; Grimm, R.; Hecker Denschlag, J.
2008-01-01
The production of ultracold molecules with their rich internal structure is currently attracting considerable interest1, 2, 3, 4. For future experiments, it will be important to efficiently transfer these molecules from their initial internal quantum state at production to other quantum states of in
Topological superconducting phase and Majorana bound states in Shiba chains
Pientka, Falko; Peng, Yang; Glazman, Leonid; von Oppen, Felix
2015-12-01
Chains of magnetic adatoms on a conventional superconducting substrate constitute a promising venue for realizing topological superconductivity and Majorana end states. Here, we give a brief overview over recent attempts to describe these systems theoretically, emphasizing how the topological phase emerges from the physics of individual magnetic impurities and their associated Shiba states.
An Improved Lower Bound Limit State Optimisation Algorithm
DEFF Research Database (Denmark)
Frier, Christian; Damkilde, Lars
2010-01-01
Limit State analysis has been used in manual design methods for decades e.g. the yield line theory for concrete slabs.......Limit State analysis has been used in manual design methods for decades e.g. the yield line theory for concrete slabs....
The dynamical gluon mass in the massless bound-state formalism
Ibanez, David
2014-01-01
We describe the phenomenon of dynamical gluon mass generation within the massless bound-state formalism, which constitutes the general framework for the systematic implementation of the Schwinger mechanism in non-Abelian gauge theories. The main ingredient of this formalism is the dynamical formation of bound states with vanishing mass, which gives rise to effective vertices containing massless poles; these vertices, in turn, trigger the Schwinger mechanism, and allow for the gauge-invariant generation of an effective gluon mass. In this particular approach, the gluon mass is directly related to quantities that are intrinsic to the bound-state formation itself, such as the "transition amplitude" and the corresponding "bound-state wave-function". Specifically, a set of powerful relations discussed in the text, allows one to determine the dynamical evolution of the gluon mass through a Bethe-Salpeter equation, which controls the dynamics of the relevant wave-function. In addition, it is possible to demonstrate ...
Dvornikov, Maxim
2011-01-01
I reply here to the comment of Dr Shmatov on my recent work and demonstrate the invalidity of his criticism of the classical physics description of the formation of bound states of electrons participating in spherically symmetric oscillations of plasma.
Quark-antiquark bound-state spectroscopy and QCD
Energy Technology Data Exchange (ETDEWEB)
Bloom, E.D.
1982-11-01
The discussion covers quarks as we know them, the classification of ordinary mesons in terms of constituent quarks, hidden charm states and charmed mesons, bottom quarks, positronium as a model for quarti q, quantum chromodynamics and its foundation in experiment, the charmonium model, the mass of states, fine structure and hyperfine structure, classification, widths of states, rate and multipolarity of gamma transitions, questions about bottom, leptonic widths and the determination of Q/sub b/, the mass splitting of the n/sup 3/S/sub 1/ states, the center of gravity of the masses of the n/sup 3/P; states, n/sup 3/ P; fine structure and classification, branching ratios for upsilon' ..-->.. tau chi/sub 6j/ and the tau cascade reactions, hyperfine splitting, and top. (GHT)
Impurity bound states in fully gapped d-wave superconductors with subdominant order parameters
Mashkoori, Mahdi; Björnson, Kristofer; Black-Schaffer, Annica M.
2017-01-01
Impurities in superconductors and their induced bound states are important both for engineering novel states such as Majorana zero-energy modes and for probing bulk properties of the superconducting state. The high-temperature cuprates offer a clear advantage in a much larger superconducting order parameter, but the nodal energy spectrum of a pure d-wave superconductor only allows virtual bound states. Fully gapped d-wave superconducting states have, however, been proposed in several cuprate systems thanks to subdominant order parameters producing d + is- or d + id′-wave superconducting states. Here we study both magnetic and potential impurities in these fully gapped d-wave superconductors. Using analytical T-matrix and complementary numerical tight-binding lattice calculations, we show that magnetic and potential impurities behave fundamentally different in d + is- and d + id′-wave superconductors. In a d + is-wave superconductor, there are no bound states for potential impurities, while a magnetic impurity produces one pair of bound states, with a zero-energy level crossing at a finite scattering strength. On the other hand, a d + id′-wave symmetry always gives rise to two pairs of bound states and only produce a reachable zero-energy level crossing if the normal state has a strong particle-hole asymmetry. PMID:28281570
Impurity bound states in fully gapped d-wave superconductors with subdominant order parameters.
Mashkoori, Mahdi; Björnson, Kristofer; Black-Schaffer, Annica M
2017-03-10
Impurities in superconductors and their induced bound states are important both for engineering novel states such as Majorana zero-energy modes and for probing bulk properties of the superconducting state. The high-temperature cuprates offer a clear advantage in a much larger superconducting order parameter, but the nodal energy spectrum of a pure d-wave superconductor only allows virtual bound states. Fully gapped d-wave superconducting states have, however, been proposed in several cuprate systems thanks to subdominant order parameters producing d + is- or d + id'-wave superconducting states. Here we study both magnetic and potential impurities in these fully gapped d-wave superconductors. Using analytical T-matrix and complementary numerical tight-binding lattice calculations, we show that magnetic and potential impurities behave fundamentally different in d + is- and d + id'-wave superconductors. In a d + is-wave superconductor, there are no bound states for potential impurities, while a magnetic impurity produces one pair of bound states, with a zero-energy level crossing at a finite scattering strength. On the other hand, a d + id'-wave symmetry always gives rise to two pairs of bound states and only produce a reachable zero-energy level crossing if the normal state has a strong particle-hole asymmetry.
Bauschlicher, C. W., Jr.; Silver, D. M.; Yarkony, D. R.
1980-01-01
The paper presents the multiconfiguration-self-consistent (MCSCF) and configuration state functions (CSF) for the low-lying electronic states of MgO. It was shown that simple description of these states was possible provided the 1 Sigma(+) states are individually optimized at the MCSCF level, noting that the 1(3 Sigma)(+) and 2(1 Sigma)(+) states which nominally result from the same electron occupation are separated energetically. The molecular orbitals obtained at this level of approximation should provide a useful starting point for extended configuration interaction calculations since they have been optimized for the particular states of interest.
Bauschlicher, C. W., Jr.; Silver, D. M.; Yarkony, D. R.
1980-01-01
The paper presents the multiconfiguration-self-consistent (MCSCF) and configuration state functions (CSF) for the low-lying electronic states of MgO. It was shown that simple description of these states was possible provided the 1 Sigma(+) states are individually optimized at the MCSCF level, noting that the 1(3 Sigma)(+) and 2(1 Sigma)(+) states which nominally result from the same electron occupation are separated energetically. The molecular orbitals obtained at this level of approximation should provide a useful starting point for extended configuration interaction calculations since they have been optimized for the particular states of interest.
Electron impact excitation and assignment of the low-lying electronic states of N2O
Hall, R. I.; Chutjian, A.; Trajmar, S.
1973-01-01
Electron scattering spectra of nitrous oxide are reported in the 5- to 10-eV energy-loss range at scattering angles of 20, 30, 90, and 130 deg at a residual energy of 7.0 eV; and at residual energies of 10.0, 2.0, 1.0, 0.6, and 0.2 eV at a scattering angle of 90 deg. Several new distinct and overlapping continua are observed to lie in this energy-loss range. The experimental spectra are discussed in the light of semiempirical INDO calculations of Chutjian and Segal (1972) of the vertical transition energies of N2O. An assignment of the symmetries of the observed excitations consistent with the experimental and theoretical data is suggested.
Electron-impact excitation of the low-lying electronic states of HCN
Chutjian, A.; Tanaka, H.; Srivastava, S. K.; Wicke, B. G.
1977-01-01
The first study of the low-energy electron-impact excitation of low-lying electronic transitions in the HCN molecule is reported. Measurements were made at incident electron energies of 11.6 and 21.6 eV in the energy-loss range of 3-10 eV, and at scattering angles of 20-130 deg. Inelastic scattering spectra were placed on the absolute cross-section scale by determining first the ratio of inelastic-to-elastic scattering cross sections, and then separately measuring the absolute elastic scattering cross section. Several new electronic transitions are observed which are intrinsically overlapped in the molecule itself. Assignments of these electronic transitions are suggested. These assignments are based on present spectroscopic and cross-sections measurements, high-energy electron scattering spectra, optical absorption spectra, and ab initio molecular orbital calculations.
Raman scattering from a superconductivity-induced bound state in MgB2.
Zeyher, R
2003-03-14
It is shown that the sharp peak in the E(2g) Raman spectrum of superconducting MgB2 is due to a bound state caused by the electron-phonon coupling. Our theory explains why this peak appears only in the spectra with E(2g) symmetry and only in the sigma but not the pi bands. The properties of the bound state and the Raman spectrum are investigated, also in the presence of impurity scattering.
Bound States and Band Structure - a Unified Treatment through the Quantum Hamilton - Jacobi Approach
Ranjani, S S; Panigrahi, P K
2005-01-01
We analyze the Scarf potential, which exhibits both discrete energy bound states and energy bands, through the quantum Hamilton-Jacobi approach. The singularity structure and the boundary conditions in the above approach, naturally isolate the bound and periodic states, once the problem is mapped to the zero energy sector of another quasi-exactly solvable quantum problem. The energy eigenvalues are obtained without having to solve for the corresponding eigenfunctions explicitly. We also demonstrate how to find the eigenfunctions through this method.
Spectroscopy of eta'-nucleus bound states at GSI-SIS
Fujioka, Hiroyuki; Geissel, Hans; Hayano, Ryugo S; Hirenzaki, Satoru; Itoh, Satoshi; Jido, Daisuke; Metag, Volker; Nagahiro, Hideko; Nanova, Mariana; Nishi, Takahiro; Okochi, Kota; Outa, Haruhiko; Suzuki, Ken; Suzuki, Takatoshi; Tanaka, Yoshiki K; Weick, Helmut
2012-01-01
The eta' meson mass may be reduced due to partial restoration of chiral symmetry. If this is the case, an eta'-nucleus system may form a nuclear bound state. We plan to carry out a missing-mass spectroscopy with the 12C(p,d) reaction at GSI-SIS. Peak structures corresponding to such a bound state may be observed even in an inclusive measurement, if the decay width is narrow enough.
Spectroscopy of η′-nucleus bound states at GSI-SIS
Directory of Open Access Journals (Sweden)
Outa Haruhiko
2012-12-01
Full Text Available The η′ meson mass may be reduced due to partial restoration of chiral symmetry. If this is the case, an η′-nucleus system may form a nuclear bound state.We plan to carry out a missing-mass spectroscopy experiment with the 12C(p,d reaction at GSI-SIS. Peak structures corresponding to such a bound state may be observed even in an inclusive measurement, if the decay width is narrow enough.
Eta bound states in nuclei: a probe of flavour-singlet dynamics
Energy Technology Data Exchange (ETDEWEB)
Steven D. Bass; Anthony W. Thomas
2005-07-01
We argue that eta bound states in nuclei are sensitive to the singlet component in the eta. The bigger the singlet component, the more attraction and the greater the binding. Thus, measurements of eta bound states will yield new information about axial U(1) dynamics and glue in mesons. Eta - etaprime mixing plays an important role in understanding the value of the eta-nucleon scattering length.
Institute of Scientific and Technical Information of China (English)
LIU Hui; HOU De-Fu; LI Jia-Rong
2009-01-01
We investigate the in-medium interparticle potential of hot gauge system with bound states by employing the QED and scalar QED coupling. At the finite temperature an oscillatory behavior of the potential has been found as well as its variation in terms of different free parameters. We expect the competition among the parameters will lead to an appropriate interparticle potential, which could be extended to discuss the fluid properties of QGP with scalar bound states.
Exact bound state solutions of the Klein-Gordon particle in Hulthén potential
Institute of Scientific and Technical Information of China (English)
Zhang Min-Cang
2008-01-01
In this paper,the Klein-Gordon equation with the spherical symmetric Hulthén potential is turned into a hypergeometric equation and is solved in the framework of function analysis exactly.The corresponding bound state solutions are expressed in terms of the hypergeometric function,and the energy spectrum of the bound states is obtained as a solution to a given equation by boundary constraints.
Calculations of bar K-nuclear quasi-bound states using chiral bar KN amplitudes
Mareš, J.; Barnea, N.; Cieplý, A.; Friedman, E.; Gal, A.; Gazda, D.
2014-03-01
We review our recent calculations of K- quasi-bound states in nuclear systems using subthreshold energy dependent chiral bar KN amplitudes. Strong energy dependence of the scattering amplitudes requires self-consistent evaluation of the involved bar KN interactions. In view of sizable widths predicted by our calculations, an unambiguous identification of K--nuclear quasi-bound states in ongoing experimental searches would be difficult.
Hyperspherical three-body model calculation for the bound $^{1,3}$S-states of Coulombic systems
Khan, Md Abdul
2014-01-01
In this paper, hyperspherical three-body model formalism has been applied for the calculation energies of the low-lying bound $^{1,3}$S (L=0)-states of neutral helium and helium like Coulombic three-body systems having nuclear charge (Z) in the range Z=2 to Z=92. The calculation of the coupling potential matrix elements of the two-body potentials has been simplified by the introduction of Raynal-Revai Coefficients (RRC). The three-body wave function in the Schr\\H{o}dinger equation when expanded in terms of hyperpherical harmonics (HH), leads to an infinite set of coupled differential equation (CDE). For practical reason the infinite set of CDE is truncated to a finite set and are solved by an exact numerical method known as renormalized Numerov method (RNM) to get the energy solution (E). The calculated energy is compared with the ones of the literature.
Transfer Function Bounds for Partial-unit-memory Convolutional Codes Based on Reduced State Diagram
Lee, P. J.
1984-01-01
The performance of a coding system consisting of a convolutional encoder and a Viterbi decoder is analytically found by the well-known transfer function bounding technique. For the partial-unit-memory byte-oriented convolutional encoder with m sub 0 binary memory cells and (k sub 0 m sub 0) inputs, a state diagram of 2(K) (sub 0) was for the transfer function bound. A reduced state diagram of (2 (m sub 0) +1) is used for easy evaluation of transfer function bounds for partial-unit-memory codes.
Low-lying electronic states of M(3)O(9)(-) and M(3)O(9)(2-) (M = Mo, W).
Li, Shenggang; Dixon, David A
2007-11-01
Multiple low-lying electronic states of M(3)O(9)(-) and M(3)O(9)(2-) (M = Mo, W) arise from the occupation of the near-degenerate low-lying virtual orbitals in the neutral clusters. We used density functional theory (DFT) and coupled cluster theory (CCSD(T)) with correlation consistent basis sets to study the structures and energetics of the electronic states of these anions. The adiabatic and vertical electron detachment energies (ADEs and VDEs) of the anionic clusters were calculated with 27 exchange-correlation functionals including one local spin density approximation functional, 13 generalized gradient approximation (GGA) functionals, and 13 hybrid GGA functionals, as well as the CCSD(T) method. For M(3)O(9)(-), CCSD(T) and nearly all of the DFT exchange-correlation functionals studied predict the (2)A(1) state arising from the Jahn-Teller distortion due to singly occupying the degenerate e' orbital to be lower in energy than the (2)A(1)' state arising from singly occupying the nondegenerate a(1)' orbital. For W(3)O(9)(-), the (2)A(1) state was predicted to have essentially the same energy as the (2)A(1)' state at the CCSD(T) level with core-valence correlation corrections included and to be higher in energy or essentially isoenergetic with most DFT methods. The calculated VDEs from the CCSD(T) method are in reasonable agreement with the experimental values for both electronic states if estimates for the corrections due to basis set incompleteness are included. For M(3)O(9)(2-), the singlet state arising from doubly occupying the nondegenerate a(1)' orbital was predicted to be the most stable state for both M = Mo and W. However, whereas M(3)O(9)(2-) was predicted to be less stable than M(3)O(9)(-), W(3)O(9)(2-) was predicted to be more stable than W(3)O(9)(-).
Scaling and universality in two dimensions: three-body bound states with short-ranged interactions
Energy Technology Data Exchange (ETDEWEB)
Bellotti, F F; Frederico, T [Instituto Tecnologico de Aeronautica, DCTA, 12.228-900 Sao Jose dos Campos, SP (Brazil); Yamashita, M T [Instituto de Fisica Teorica, UNESP-Univ Estadual Paulista, CP 70532-2, CEP 01156-970, Sao Paulo, SP (Brazil); Fedorov, D V; Jensen, A S; Zinner, N T, E-mail: zinner@phys.au.dk [Department of Physics and Astronomy-Aarhus University, Ny Munkegade, bygn. 1520, DK-8000 Arhus C (Denmark)
2011-10-28
The momentum space zero-range model is used to investigate universal properties of three interacting particles confined to two dimensions. The pertinent equations are first formulated for a system of two identical and one distinct particle and the two different two-body subsystems are characterized by two-body energies and masses. The three-body energy in units of one of the two-body energies is a universal function of the other two-body energy and the mass ratio. We derive convenient analytical formulae for calculations of the three-body energy as a function of these two independent parameters and exhibit the results as universal curves. In particular, we show that the three-body system can have any number of stable bound states. When the mass ratio of the distinct to identical particles is greater than 0.22, we find that at most two stable bound states exist, while for two heavy and one light mass an increasing number of bound states is possible. The specific number of stable bound states depends on the ratio of two-body bound state energies and on the mass ratio, and we map out an energy-mass phase diagram of the number of stable bound states. Realizable systems of both fermions and bosons are discussed in this framework.
Theoretical spectroscopy study of the low-lying electronic states of UX and UX+, X = F and Cl
Bross, David H.; Peterson, Kirk A.
2015-11-01
Spectroscopic constants (Te, re, B0, ωe, and ωexe) have been calculated for the low-lying electronic states of UF, UF+, UCl, and UCl+ using complete active space 2nd-order perturbation theory (CASPT2), with a series of correlation consistent basis sets. The latter included those based on both pseudopotential (PP) and all-electron Douglas-Kroll-Hess Hamiltonians for the U atom. Spin orbit (SO) effects were included a posteriori using the state interacting method using both PP and Breit Pauli (BP) operators, as well as from exact two-component methods for U+ and UF+. Complete basis set (CBS) limits were obtained by extrapolation where possible and the PP and BP calculations were compared at their respective CBS limits. The PP-based method was shown to be reliable in calculating spectroscopic constants, in particular when using the state interacting method with CASPT2 energies (SO-CASPT2). The two component calculations were limited by computational resources and could not include electron correlation from the nominally closed shell 6s and 6p orbitals of U. UF and UCl were both calculated to have Ω = 9/2 ground states. The first excited state of UCl was calculated to be an Ω = 7/2 state at 78 cm-1 as opposed to the same state at 435 cm-1 in UF, and the other low-lying states of UCl showed a similar compression relative to UF. Likewise, UF+ and UCl+ both have Ω = 4 ground states and the manifold of low-lying excited Ω = 3, 2, 1, 0 states was energetically closer together in UCl+ than in UF+, ranging up to 776 cm-1 in UF+ and only 438 cm-1 in UCl+. As in previous studies, the final PP-based SO-CASPT2 results for UF+ and UF agree well with experiment and are expected to be predictive for UCl and UCl+, which are reported here for the first time.
Theoretical spectroscopy study of the low-lying electronic states of UX and UX(+), X = F and Cl.
Bross, David H; Peterson, Kirk A
2015-11-14
Spectroscopic constants (Te, re, B0, ωe, and ωexe) have been calculated for the low-lying electronic states of UF, UF(+), UCl, and UCl(+) using complete active space 2nd-order perturbation theory (CASPT2), with a series of correlation consistent basis sets. The latter included those based on both pseudopotential (PP) and all-electron Douglas-Kroll-Hess Hamiltonians for the U atom. Spin orbit (SO) effects were included a posteriori using the state interacting method using both PP and Breit Pauli (BP) operators, as well as from exact two-component methods for U(+) and UF(+). Complete basis set (CBS) limits were obtained by extrapolation where possible and the PP and BP calculations were compared at their respective CBS limits. The PP-based method was shown to be reliable in calculating spectroscopic constants, in particular when using the state interacting method with CASPT2 energies (SO-CASPT2). The two component calculations were limited by computational resources and could not include electron correlation from the nominally closed shell 6s and 6p orbitals of U. UF and UCl were both calculated to have Ω = 9/2 ground states. The first excited state of UCl was calculated to be an Ω = 7/2 state at 78 cm(-1) as opposed to the same state at 435 cm(-1) in UF, and the other low-lying states of UCl showed a similar compression relative to UF. Likewise, UF(+) and UCl(+) both have Ω = 4 ground states and the manifold of low-lying excited Ω = 3, 2, 1, 0 states was energetically closer together in UCl(+) than in UF(+), ranging up to 776 cm(-1) in UF(+) and only 438 cm(-1) in UCl(+). As in previous studies, the final PP-based SO-CASPT2 results for UF(+) and UF agree well with experiment and are expected to be predictive for UCl and UCl(+), which are reported here for the first time.
Theoretical spectroscopy study of the low-lying electronic states of UX and UX{sup +}, X = F and Cl
Energy Technology Data Exchange (ETDEWEB)
Bross, David H.; Peterson, Kirk A., E-mail: kipeters@wsu.edu [Department of Chemistry, Washington State University, Pullman, Washington 99164-4630 (United States)
2015-11-14
Spectroscopic constants (T{sub e}, r{sub e}, B{sub 0}, ω{sub e}, and ω{sub e}x{sub e}) have been calculated for the low-lying electronic states of UF, UF{sup +}, UCl, and UCl{sup +} using complete active space 2nd-order perturbation theory (CASPT2), with a series of correlation consistent basis sets. The latter included those based on both pseudopotential (PP) and all-electron Douglas-Kroll-Hess Hamiltonians for the U atom. Spin orbit (SO) effects were included a posteriori using the state interacting method using both PP and Breit Pauli (BP) operators, as well as from exact two-component methods for U{sup +} and UF{sup +}. Complete basis set (CBS) limits were obtained by extrapolation where possible and the PP and BP calculations were compared at their respective CBS limits. The PP-based method was shown to be reliable in calculating spectroscopic constants, in particular when using the state interacting method with CASPT2 energies (SO-CASPT2). The two component calculations were limited by computational resources and could not include electron correlation from the nominally closed shell 6s and 6p orbitals of U. UF and UCl were both calculated to have Ω = 9/2 ground states. The first excited state of UCl was calculated to be an Ω = 7/2 state at 78 cm{sup −1} as opposed to the same state at 435 cm{sup −1} in UF, and the other low-lying states of UCl showed a similar compression relative to UF. Likewise, UF{sup +} and UCl{sup +} both have Ω = 4 ground states and the manifold of low-lying excited Ω = 3, 2, 1, 0 states was energetically closer together in UCl{sup +} than in UF{sup +}, ranging up to 776 cm{sup −1} in UF{sup +} and only 438 cm{sup −1} in UCl{sup +}. As in previous studies, the final PP-based SO-CASPT2 results for UF{sup +} and UF agree well with experiment and are expected to be predictive for UCl and UCl{sup +}, which are reported here for the first time.
QQqq Four-Quark Bound States in Chiral SU(3) Quark Model
Institute of Scientific and Technical Information of China (English)
ZHANG Ming; ZHANG Hai-Xia; ZHANG Zong-Ye
2008-01-01
The possibility of QQqq heavy-light four-quark bound states has been analyzed by means of the chiral SU(3) quark model, where Q is the heavy quark (c or b) and q is the light quark (u, d, or s). We obtain a bound state for the bbnn configuration with quantum number JP=1+, I=0 and for the ccnn (JP=1+, I=0) configuration, which is not bound but slightly above the D*D* threshold (n is u or d quark). Meanwhile, we also conclude that a weakly bound state in bbnn system can also be found without considering the chiral quark interactions between the two light quarks, yet its binding energy is weaker than that with the chiral quark interactions.
An Improved Lower Bound Limit State Optimisation Algorithm
DEFF Research Database (Denmark)
Frier, Christian; Damkilde, Lars
2010-01-01
Limit State analysis has been used in engineering practice for many years e.g. the yield-line method for concrete slabs and slip-line solutions in geotechnics. In the recent years there has been an increased interest in numerical Limit State analysis, and today algorithms take into account the non......-linear yield criteria. The aim of the paper is to refine an earlier presented effective method which reduces the number of optimisation variables considerably by eliminating the equilibrium equations a priori and improvements are made on the interior point optimisation algorithm....
Koseki, Shiro; Matsushita, Takeshi; Gordon, Mark S
2006-02-23
The dissociation curves of low-lying spin-mixed states in monohydrides of groups 6 and 7 were calculated by using an effective core potential (ECP) approach. This approach is based on the multiconfiguration self-consistent field (MCSCF) method, followed by first-order configuration interaction (FOCI) calculations, in which the method employs an ECP basis set proposed by Stevens and co-workers (SBKJC) augmented by a set of polarization functions. Spin-orbit coupling (SOC) effects are estimated within the one-electron approximation by using effective nuclear charges, since SOC splittings obtained with the full Breit-Pauli Hamitonian are underestimated when ECP basis sets are used. The ground states of group 6 hydrides have Omega = (1)/(2)(X(6)Sigma(+)(1/2)), where Omega is the z component of the total angular momentum quantum number. Although the ground states of group 7 hydrides have Omega = 0(+), their main adiabatic components are different; the ground state in MnH originates from the lowest (7)Sigma(+), while in TcH and ReH the main component of the ground state is the lowest (5)Sigma(+). The present paper reports a comprehensive set of theoretical results including the dissociation energies, equilibrium distances, electronic transition energies, harmonic frequencies, anharmonicities, and rotational constants for several low-lying spin-mixed states in these hydrides. Transition dipole moments were also computed among the spin-mixed states and large peak positions of electronic transitions are suggested theoretically for these hydrides. The periodic trends of physical properties of metal hydrides are discussed, based on the results reported in this and other recent studies.
Is the exotic X(5568) a bound state?
Energy Technology Data Exchange (ETDEWEB)
Chen, Xiaoyun; Ping, Jialun [Nanjing Normal University, Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems, Nanjing (China)
2016-06-15
Stimulated by the recent observation of the exotic X(5568) state by the D0 Collaboration, we study the four-quark system us anti b anti d with quantum numbers J{sup P} = 0{sup +} in the framework of the chiral quark model. Two structures, diquark-antidiquark and meson-meson, with all possible color configurations are investigated by using the Gaussian expansion method. The results show that the energies of the tetraquark states with diquark-antiquark structure are too high to be candidates of X(5568), and no molecular structure can be formed in our calculations. The calculation is also extended to the four-quark system us anti c anti d and the same results as that of us anti b anti d are obtained. (orig.)
Bethe-Salpeter bound-state structure in Minkowski space
Gutierrez, C; Frederico, T; Salmè, G; Viviani, M; Tomio, Lauro
2016-01-01
The quantitative investigation of the scalar Bethe-Salpeter equation in Minkowski space, within the ladder-approximation framework, is extended to include the excited states. This study has been carried out for an interacting system composed by two massive bosons exchanging a massive scalar, by adopting (i) the Nakanishi integral representation of the Bethe-Salpeter amplitude, and (ii) the formally exact projection onto the null plane. Our analysis, on one hand, confirms the reliability of the method already applied to the ground state and, on the other one, extends the investigation from the valence distribution in momentum space to the corresponding quantity in the impact-parameter space, pointing out some relevant features, like (i) the equivalence between Minkowski and Euclidean transverse-momentum amplitudes, and (ii) the leading exponential fall-off of the valence wave function in the impact-parameter space.
Bethe–Salpeter bound-state structure in Minkowski space
Energy Technology Data Exchange (ETDEWEB)
Gutierrez, C. [Instituto de Física Teórica, Universidade Estadual Paulista, 01156-970 São Paulo, SP (Brazil); Gigante, V.; Frederico, T. [Instituto Tecnológico de Aeronáutica, DCTA, 12.228-900 São José dos Campos, SP (Brazil); Salmè, G. [Istituto Nazionale di Fisica Nucleare, Sezione di Roma, P.le A. Moro 2, 00185 Roma (Italy); Viviani, M. [Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, Largo Pontecorvo 3, 56100 Pisa (Italy); Tomio, Lauro, E-mail: tomio@ift.unesp.br [Instituto de Física Teórica, Universidade Estadual Paulista, 01156-970 São Paulo, SP (Brazil); Instituto Tecnológico de Aeronáutica, DCTA, 12.228-900 São José dos Campos, SP (Brazil)
2016-08-10
The quantitative investigation of the scalar Bethe–Salpeter equation in Minkowski space, within the ladder-approximation framework, is extended to include the excited states. This study has been carried out for an interacting system composed by two massive bosons exchanging a massive scalar, by adopting (i) the Nakanishi integral representation of the Bethe–Salpeter amplitude, and (ii) the formally exact projection onto the null plane. Our analysis, on one hand, confirms the reliability of the method already applied to the ground state and, on the other one, extends the investigation from the valence distribution in momentum space to the corresponding quantity in the impact-parameter space, pointing out some relevant features, like (i) the equivalence between Minkowski and Euclidean transverse-momentum amplitudes, and (ii) the leading exponential fall-off of the valence wave function in the impact-parameter space.
Andreev Spectra and Subgap Bound States in Multiband Superconductors
Golubov, A. A.; Brinkman, A.; Tanaka, Yukio; Mazin, I.I.; Dolgov, O. V.
2009-01-01
The theory of Andreev conductance is formulated for junctions involving normal metals (N) and multiband superconductors (S) and applied to the case of superconductors with nodeless extended $s_{\\pm}$-wave order parameter symmetry, as possibly realized in the recently discovered ferro pnictides. We find qualitative differences from tunneling into s-wave or d-wave superconductors that may help to identify such a state. First, interband interference leads to a suppression of Andreev reflection i...
Institute of Scientific and Technical Information of China (English)
Yao Jiang-Ming; Meng Jie; D. Pena Arteaga; P. Ring
2008-01-01
A full three-dimensional angular momentum projection on top of a triaxial relativistic mean-field calculation is implemented for the first time. The underlying Lagrangian is a point coupling model and pairing correlations are taken into account by a monopole force. This method is applied for the low-lying excited states in 24Mg. Good agreement with the experimental data is found for the ground state properties. A minimum in the potential energy surface for the 2+ state, with β≈ 0.55, γ≈ 10°, is used as the basis to investigate the rotational energyspectrum as well as the corresponding B(E2) transition probabilities as compared to the available data.
The low-lying 2-sigma-minus states of OH
Van Dishoeck, E. F.; Langhoff, S. R.; Dalgarno, A.
1983-01-01
The configuration-interaction method is used to determine the electronic wave functions of the two lowest 2-sigma-minus states of OH using four different atomic orbital basis sets. Potential energy curves, transition moments, oscillator strengths, and photodissociation cross sections are obtained. Electronic transition dipole moments connecting the excited 1 2-sigma-minus and 2(D)2-sigma-minus states with each other and with the ground chi-2-pi state are presented as functions of internuclear distance. The theoretical absorption oscillator strengths for the D-2-sigma-minus(v prime = 0) from chi-2-pi(v double prime = 0) transition are in good agreement with the empirical value derived from astronomical measurement. The photodissociation cross sections for absorption from the v prime = 0, 1, and 2 levels of the ground state into the continuum of the 1 2-sigma-minus state are calculated, and the interstellar and cometary photodissociation rates are derived.
Lifetimes and collectivity of low-lying states in 115Sn
Lobach, Yu. N.; Käubler, L.; Schwengner, R.; Pasternak, A. A.
1999-04-01
The lifetimes of excited states in 115Sn have been measured using the Doppler shift attenuation method in the reaction 113Cd(α,2nγ) at Eα=27.2 MeV. Lifetimes were obtained for 18 states and lifetime limits for 6 states with Ex<=4 MeV and J<=23/2. The experimentally obtained B(σL) values for transitions deexciting positive-parity states are compared with calculations in the framework of the Bardeen-Cooper-Schrieffer quasiparticle model and the interacting boson fermion model, whereas the values for transitions between negative-parity states are discussed qualitatively within a core-particle coupling picture. The value of B(E2)=3.5(11) Weisskopf units (W.u.) for the transition linking the 19/2- state of the intruder νh11/2π2p2h band to the 15/2- state of the νh11/2⊗2+1 multiplet strongly supports the configuration νh11/2π(g-29/2g27/2) ascribed to this band.
Observation of a low-lying neutron-unbound state in 19C
Thoennessen, M; Badger, N S; Baumann, T; Bazin, D; Bennett, M; Brown, J; Christian, G; DeYoung, P A; Finck, J E; Gardner, M; Hook, E A; Luther, B; Meyer, D A; Mosby, M; Rogers, W F; Smith, J K; Spyrou, A; Strongman, M J
2013-01-01
Proton removal reactions from a secondary 22N beam were utilized to populate unbound states in neutron-rich carbon isotopes. Neutrons were measured with the Modular Neutron Array (MoNA) in coincidence with carbon fragments. A resonance with a decay energy of 76(14) keV was observed in the system 18C+n corresponding to a state in 19C at an excitation energy of 653(95)keV. This resonance could correspond to the first 5/2+ state which was recently speculated to be unbound in order to describe 1n and 2n removal cross section measurements from 20C.
Alpha clustering in $^{28}$Si probed through the identification of high-lying $0^+$ states
Adsley, P; Cseh, J; Dimitriova, S S; Brummer, J W; Li, K C W; Marin-Lambarri, D J; Lukyanov, K; Kheswa, N Y; Neveling, R; Papka, P; Pellegri, L; Pesudo, V; Pool, L C; Riczu, G; Smit, F D; van Zyl, J J; Zemlyanaya, E
2016-01-01
Aspects of nuclear structure in alpha-conjugate nuclei have long been associated with alpha clustering, including the existence of superdeformed bands. In this paper, an alpha-particle inelastic scattering experiment investigating the location of $0^+$ states in $^{28}$Si is reported in an attempt to locate possible cluster states. The results are compared to a semi-microscopic model which shows good agreement with the data, and supports the assignment of a newly discovered $0^+$ state as the band-head of a previously observed superdeformed band in $^{28}$Si
Lifetime measurements of high-lying short lived states in {sup 69}As
Energy Technology Data Exchange (ETDEWEB)
Matejska-Minda, M.; Bednarczyk, P.; Fornal, B.; Ciemala, M.; Kmiecik, M.; Krzysiek, M.; Maj, A.; Meczynski, W.; Myalski, S.; Styczen, J.; Zieblinski, M.; Angelis, G. de; Huyuk, T.; Michelagnoli, C.; Sahin, E.; Aydin, S.; Farnea, E.; Menegazzo, R.; Recchia, F.; Ur, C. A. [Institute of Nuclear Physics, Polish Academy of Sciences, Krakow (Poland); INFN, Laboratori Nazionali di Legnaro, Legnaro (Italy); Dipartimento di Fisica e INFN Padova (Italy); Dipartimento di Fisica e INFN Milano (Italy); Heavy Ion Laboratory, University of Warsaw (Poland); University of York (United Kingdom); and others
2012-10-20
Lifetimes of high-spin states in {sup 69}As have been measured using Doppler shift attenuation technique with the GASP and RFD setup. The determined transition probabilities indicate large deformation associated with some rotational bands in this nucleus.
Free energy barrier for melittin reorientation from a membrane-bound state to a transmembrane state
Irudayam, Sheeba J; Berkowitz, Max L
2013-01-01
An important step in a phospholipid membrane pore formation by melittin antimicrobial peptide is a reorientation of the peptide from a surface into a transmembrane conformation. In this work we perform umbrella sampling simulations to calculate the potential of mean force (PMF) for the reorientation of melittin from a surface-bound state to a transmembrane state and provide a molecular level insight into understanding peptide and lipid properties that influence the existence of the free energy barrier. The PMFs were calculated for a peptide to lipid (P/L) ratio of 1/128 and 4/128. We observe that the free energy barrier is reduced when the P/L ratio increased. In addition, we study the cooperative effect; specifically we investigate if the barrier is smaller for a second melittin reorientation, given that another neighboring melittin was already in the transmembrane state. We observe that indeed the barrier of the PMF curve is reduced in this case, thus confirming the presence of a cooperative effect.
Mizuyama, Kazuhito
2013-01-01
The proton inelastic scattering of $^{24}$O($p,p'$) at 62 MeV/nucleon is described by a self-consistent microscopic calculation with the continuum particle-vibration coupling (cPVC) method. The SLy5, SkM*, and SGII parameters are adopted as an effective nucleon-nucleon interaction. For all the parameters, the cPVC calculation reproduces very well the first peak at 4.65 MeV in the $^{24}$O excitation energy spectrum as well as its angular distribution. The role of the cPVC self-energy strongly depends on the effective interactions. The higher-lying strength around 7.3 MeV is suggested to be a superposition of the $3^-$ and $4^+$ states by the results with SLy5 and SGII, whereas the SkM* calculation indicates it is a pure $3^-$ state. This difference gives a rather strong interaction dependence of the angular distribution corresponding to the higher-lying strength.
Spectroscopic Parameter and Molecular Constant Investigations on Low-Lying States of BeF Radical
Directory of Open Access Journals (Sweden)
Jin Feng Sun
2012-02-01
Full Text Available The potential energy curves (PECs of X2Σ+, A2Πr and B2Σ+ states of BeF radical have been investigated using the complete active space self-consistent-field (CASSCF method, followed by the highly accurate valence internally contracted multireference configuration interaction (MRCI approach at the correlation-consistent basis sets, cc-pV5Z for Be and aug-cc-pV6Z for F. Based on the PECs of X2Σ+, A2Πr and B2Σ+ states, the spectroscopic parameters (De, Re, ωe, ωeχe, αe and Be have also been determined in the present work. With the PECs determined at the present level of theory, vibrational states have been predicted for each state when the rotational quantum number J equals zero (J = 0. The vibrational levels, inertial rotation and centrifugal distortion constants are determined for the three states, and the classical turning points are also calculated for the X2Σ+ state. Compared with the available experiments and other theories, it can be seen that the present spectroscopic parameter and molecular constant results are more fully in agreement with the experimental findings.
Emergent gauge field for a chiral bound state on curved surface
Shi, Zhe-Yu; Zhai, Hui
2017-09-01
Emergent physics is one of the most important concepts in modern physics, and one of the most intriguing examples is the emergent gauge field. Here we show that a gauge field emerges for a chiral bound state formed by two attractively interacting particles on a curved surface. We demonstrate explicitly that the center-of-mass wave function of such a deeply bound state is monopole harmonic instead of spherical harmonic, which means that the bound state experiences a magnetic monopole at the center of the sphere. This emergent gauge field is due to the coupling between the center-of-mass and the relative motion on a curved surface, and our results can be generalized to an arbitrary curved surface. This result establishes an intriguing connection between the space curvature and gauge field, and paves an alternative way to engineer a topological state with space curvature, and may be observed in a cold atom system.
Fingerprint of topological Andreev bound states in phase-dependent heat transport
Sothmann, Björn; Hankiewicz, Ewelina M.
2016-08-01
We demonstrate that phase-dependent heat currents through superconductor-topological insulator Josephson junctions provide a useful tool to probe the existence of topological Andreev bound states, even for multichannel surface states. We predict that in the tunneling regime topological Andreev bound states lead to a minimum of the thermal conductance for a phase difference ϕ =π , in clear contrast to a maximum of the thermal conductance at ϕ =π that occurs for trivial Andreev bound states in superconductor-normal-metal tunnel junctions. This opens up the possibility that phase-dependent heat transport can distinguish between topologically trivial and nontrivial 4 π modes. Furthermore, we propose a superconducting quantum interference device geometry where phase-dependent heat currents can be measured using available experimental technology.
Durán, Ruth; Guillén, Jorge; Ruiz, Antonio; Jiménez, José A.; Sagristà, Enric
2016-12-01
The geomorphological evolution of a low-lying, micro-tidal sandy beach in the western Mediterranean, Pals beach, was characterized using airborne Light Detection and Ranging (LiDAR) data. Data were collected in prior to and six months after the impact of an extreme storm with a return period of approx. 50 years, with the aim of characterizing the beach's response to the storm. The use of repeated high-resolution topographic data to quantify beach geomorphic changes has allowed assessment of the accuracy of different proxies for estimating beach volume changes. Results revealed that changes in the shoreline position cannot accurately reproduce beach volume changes on low-lying beaches where overwash processes are significant. Observations also suggested that volume estimations from beach profiles do not accurately represent subaerial volume changes at large profile distances on beaches with significant alongshore geomorphological variability. Accordingly, the segmentation of the beach into regularly spaced bins is proposed to assess alongshore variations in the beach volume with the accuracy of the topographic data. The morphological evolution of Pals beach during the study period showed a net shoreline retreat (- 4 m) and a significant sediment gain on the subaerial beach (+ 7.5 m3/m). The net gain of sediment is mostly due to the impact of the extreme storm, driving significant overwash processes that transport sediment landwards, increasing volume on the backshore and dunes. The increase of volume on the foreshore and the presence of cuspate morphologies along the shoreline also evidence post-storm beach recovery. Observed morphological changes exhibit a high variability along the beach related to variations in beach morphology. Changes in the morphology and migration of megacusps result in a high variability in the shoreline position and foreshore volume changes. On the other hand, larger morphological changes on the backshore and larger inundation distances
Tunable Plasmonic Reflection by Bound 1D Electron States in a 2D Dirac Metal
Jiang, B.-Y.; Ni, G. X.; Pan, C.; Fei, Z.; Cheng, B.; Lau, C. N.; Bockrath, M.; Basov, D. N.; Fogler, M. M.
2016-08-01
We show that the surface plasmons of a two-dimensional Dirac metal such as graphene can be reflected by linelike perturbations hosting one-dimensional electron states. The reflection originates from a strong enhancement of the local optical conductivity caused by optical transitions involving these bound states. We propose that the bound states can be systematically created, controlled, and liquidated by an ultranarrow electrostatic gate. Using infrared nanoimaging, we obtain experimental evidence for the locally enhanced conductivity of graphene induced by a carbon nanotube gate, which supports this theoretical concept.
Tunable Plasmonic Reflection by Bound 1D Electron States in a 2D Dirac Metal.
Jiang, B-Y; Ni, G X; Pan, C; Fei, Z; Cheng, B; Lau, C N; Bockrath, M; Basov, D N; Fogler, M M
2016-08-19
We show that the surface plasmons of a two-dimensional Dirac metal such as graphene can be reflected by linelike perturbations hosting one-dimensional electron states. The reflection originates from a strong enhancement of the local optical conductivity caused by optical transitions involving these bound states. We propose that the bound states can be systematically created, controlled, and liquidated by an ultranarrow electrostatic gate. Using infrared nanoimaging, we obtain experimental evidence for the locally enhanced conductivity of graphene induced by a carbon nanotube gate, which supports this theoretical concept.
X(3872) and Bound State Problem of D~0(D)*~0((D)~0D*~0)
Institute of Scientific and Technical Information of China (English)
LIU Tan-rui; LIU Xiang; DENG Wei-zhen
2009-01-01
We have performed a dynamical calculation of the bound state problem of D~0(D)~(*0) by considering the pion and sigma meson exchange potential.Our preliminary analysis disfavors the molecular interpretation of X(3872) if we use the experimental D~* Dπ coupling constant g=0.59 and a reasonable cutoff around 1 GeV,which is the typical hadronic scale.In contrast,there probably exists a loosely bound S-wave B (-B)~* molecular state.Such a molecular state would be rather stable since its dominant decay mode is the radiative decay through B~*→Bγ.
Study of BB ¯*/DD ¯* bound states in a Bethe-Salpeter approach
He, Jun
2014-10-01
In this work the BB ¯*/DD ¯* system is studied in the Bethe-Salpeter approach with quasipotential approximation. In our calculation both direct and cross diagrams are included in the one-boson-exchange potential. The numerical results indicate the existence of an isoscalar bound state DD ¯* with JPC=1++, which may be related to the X(3872). In the isovector sector, no bound state is produced from the interactions of DD ¯* and BB ¯*, which suggests the molecular state explanations for Zb(10610) and Zc(3900) are excluded.
In-medium mathaccent "7016relax K- and eta -meson Interactions and Bound States
Gal, A.; Friedman, E.; Barnea, N.; Cieplý, A.; Mareš, J.; Gazda, D.
The role played by subthreshold meson-baryon dynamics is demonstrated in kaonic-atom, Kbar-nuclear and eta-nuclear bound-state calculations within in-medium models of Kbar-N and eta-N interactions. New analyses of kaonic atom data reveal appreciable multi-nucleon contributions. Calculations of eta-nuclear bound states show, in particular, that the eta-N scattering length is not a useful indicator of whether or not eta mesons bind in nuclei nor of the widths anticipated for such states.
The Low-Lying States of AlCu and AlAg
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Partridge, Harry
1994-01-01
The singlet and triplet states of AlCu and AlAg below about 32 000/cm are studied using the internally contracted multireference configuration-interaction method. A more elaborate study of the X(sup 1)Sum(sup +) ground state of AlCu is undertaken using extended Gaussian basis sets, including the effect of inner-shell correlation and including a perturbational estimate of relativistic effects. Our best estimate of the spectroscopic constants (r(sub 0), DeltaG(sub 1/2), and D(sub 0)) for the X(sup 1)Sum(sup+) state with the experimental values in parentheses are: 4.416(4.420) a(sub 0), 295 (294) /cm, and 2.318 (2.315) eV. The calculations definitively assign the upper state in the observed transition at 14 892/cm to the lowest (sup 1)Prod state. The calculated spectroscopic constants and radiative lifetime for the (sup 1)Prod state are in good agreement with experiment. The calculations support the tentative assignments of Behm et al. for three band systems observed in the visible region between 25 000 and 28 000 / cm. However, the computed spectroscopic constants are in very poor agreement with those deduced from an analysis of the spectra. Analogous theoretical results for AlAg suggest that the (2)(sup 3)Prod, (3)(sup 3)Prod, and (3)(sup 1)Sum(sup +) states account for the bands observed, but not assigned, by Duncan and co-workers.
The structure of low-lying states in ${}^{140}$Sm studied by Coulomb excitation
Klintefjord, M.; Görgen, A.; Bauer, C.; Bello Garrote, F.L.; Bönig, S.; Bounthong, B.; Damyanova, A.; Delaroche, J.P.; Fedosseev, V.; Fink, D.A.; Giacoppo, F.; Girod, M.; Hoff, P.; Imai, N.; Korten, W.; Larsen, A.C.; Libert, J.; Lutter, R.; Marsh, B.A.; Molkanov, P.L.; Naïdja, H.; Napiorkowski, P.; Nowacki, F.; Pakarinen, J.; Rapisarda, E.; Reiter, P.; Renstrøm, T.; Rothe, S.; Seliverstov, M.D.; Siebeck, B.; Siem, S.; Srebrny, J.; Stora, T.; Thöle, P.; Tornyi, T.G.; Tveten, G.M.; Van Duppen, P.; Vermeulen, M.J.; Voulot, D.; Warr, N.; Wenander, F.; De Witte, H.; Zielińska, M.
2016-05-02
The electromagnetic structure of $^{140}$Sm was studied in a low-energy Coulomb excitation experiment with a radioactive ion beam from the REX-ISOLDE facility at CERN. The $2^+$ and $4^+$ states of the ground-state band and a second $2^+$ state were populated by multi-step excitation. The analysis of the differential Coulomb excitation cross sections yielded reduced transition probabilities between all observed states and the spectroscopic quadrupole moment for the $2_1^+$ state. The experimental results are compared to large-scale shell model calculations and beyond-mean-field calculations based on the Gogny D1S interaction with a five-dimensional collective Hamiltonian formalism. Simpler geometric and algebraic models are also employed to interpret the experimental data. The results indicate that $^{140}$Sm shows considerable $\\gamma$ softness, but in contrast to earlier speculation no signs of shape coexistence at low excitation energy. This work sheds more light on the onset of deformation and collectivit...
Andreev and Majorana bound states in single and double quantum dot structures
Silva, Joelson F.; Vernek, E.
2016-11-01
We present a numerical study of the emergence of Majorana and Andreev bound states in a system composed of two quantum dots, one of which is coupled to a conventional superconductor, SC1, and the other connects to a topological superconductor, SC2. By controlling the interdot coupling we can drive the system from two single (uncoupled) quantum dots to double (coupled) dot system configurations. We employ a recursive Green’s function technique that provides us with numerically exact results for the local density of states of the system. We first show that in the uncoupled dot configuration (single dot behavior) the Majorana and the Andreev bound states appear in an individual dot in two completely distinct regimes. Therefore, they cannot coexist in the single quantum dot system. We then study the coexistence of these states in the coupled double dot configuration. In this situation we show that in the trivial phase of SC2, the Andreev states are bound to an individual quantum dot in the atomic regime (weak interdot coupling) or extended over the entire molecule in the molecular regime (strong interdot coupling). More interesting features are actually seen in the topological phase of SC2. In this case, in the atomic limit, the Andreev states appear bound to one of the quantum dots while a Majorana zero mode appears in the other one. In the molecular regime, on the other hand, the Andreev bound states take over the entire molecule while the Majorana state remains always bound to one of the quantum dots.
Rapisarda, P.; Trentelman, H.L.; Minh, H.B.
2013-01-01
We illustrate an algorithm that starting from the image representation of a strictly bounded-real system computes a minimal balanced state variable, from which a minimal balanced state realization is readily obtained. The algorithm stems from an iterative procedure to compute a storage function, bas
Normalization and perturbation theory for tightly bound states of the spinor Bethe-Salpeter equation
L.G. Suttorp
1976-01-01
The normalisation integrals for the tightly-bound-state solutions of the spinor Bethe-Salpeter equation that have been derived recently are evaluated. Ghost states are found to appear when the continuous parameters characterising the type of fermion-boson interaction reach a critical value. Perturba
Normalization and perturbation theory for tightly bound states of the spinor Bethe-Salpeter equation
Suttorp, L.G.
1976-01-01
The normalisation integrals for the tightly-bound-state solutions of the spinor Bethe-Salpeter equation that have been derived recently are evaluated. Ghost states are found to appear when the continuous parameters characterising the type of fermion-boson interaction reach a critical value. Perturba
Search for $\\eta$'(958)-nucleus bound states by (p,d) reaction at GSI and FAIR
Fujioka, H; Benlliure, J; Brinkmann, K -T; Friedrich, S; Geissel, H; Gellanki, J; Guo, C; Gutz, E; Haettner, E; Harakeh, M N; Hayano, R S; Higashi, Y; Hirenzaki, S; Hornung, C; Igarashi, Y; Ikeno, N; Itahashi, K; Iwasaki, M; Jido, D; Kalantar-Nayestanaki, N; Kanungo, R; Knoebel, R; Kurz, N; Metag, V; Mukha, I; Nagae, T; Nagahiro, H; Nanova, M; Nishi, T; Ong, H J; Pietri, S; Prochazka, A; Rappold, C; Reiter, M P; Rodríguez-Sánchez, J L; Scheidenberger, C; Simon, H; Sitar, B; Strmen, P; Sun, B; Suzuki, K; Szarka, I; Takechi, M; Tanaka, Y K; Tanihata, I; Terashima, S; Watanabe, Y N; Weick, H; Widmann, E; Winfield, J S; Xu, X; Yamakami, H; Zhao, J
2015-01-01
The mass of the {\\eta}' meson is theoretically expected to be reduced at finite density, which indicates the existence of {\\eta}'-nucleus bound states. To investigate these states, we perform missing-mass spectroscopy for the (p, d) reaction near the {\\eta}' production threshold. The overview of the experimental situation is given and the current status is discussed.
Observation of a low-lying neutron-unbound state in {sup 19}C
Energy Technology Data Exchange (ETDEWEB)
Thoennessen, M., E-mail: thoennessen@nscl.msu.edu [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Mosby, S. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Badger, N.S. [Department of Physics, Rhodes College, Memphis, TN 38112 (United States); Baumann, T.; Bazin, D. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States); Bennett, M. [Department of Physics, Westmont College, Santa Barbara, CA 93108 (United States); Brown, J. [Department of Physics, Wabash College, Crawfordsville, IN 47933 (United States); Christian, G. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); DeYoung, P.A. [Department of Physics, Hope College, Holland, MI 49423 (United States); Finck, J.E. [Department of Physics, Central Michigan University, Mt. Pleasant, MI 48859 (United States); Gardner, M. [Department of Physics, Westmont College, Santa Barbara, CA 93108 (United States); Hook, E.A. [Department of Physics, Rhodes College, Memphis, TN 38112 (United States); Luther, B. [Department of Physics, Concordia College, Moorhead, MN 56562 (United States); Meyer, D.A. [Department of Physics, Rhodes College, Memphis, TN 38112 (United States); Mosby, M. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Rogers, W.F. [Department of Physics, Westmont College, Santa Barbara, CA 93108 (United States); and others
2013-08-21
Proton removal reactions from a secondary {sup 22}N beam were utilized to populate unbound states in neutron-rich carbon isotopes. Neutrons were measured with the Modular Neutron Array (MoNA) in coincidence with carbon fragments. A resonance with a decay energy of 76(14) keV was observed in the system {sup 18}C+n corresponding to a state in {sup 19}C at an excitation energy of 653(95) keV. This resonance could correspond to the first 5/2{sup +} state which was recently speculated to be unbound in order to describe 1n and 2n removal cross section measurements from {sup 20}C.
Explicit formula for the Holevo bound for two-parameter qubit-state estimation problem
Suzuki, Jun
2016-04-01
The main contribution of this paper is to derive an explicit expression for the fundamental precision bound, the Holevo bound, for estimating any two-parameter family of qubit mixed-states in terms of quantum versions of Fisher information. The obtained formula depends solely on the symmetric logarithmic derivative (SLD), the right logarithmic derivative (RLD) Fisher information, and a given weight matrix. This result immediately provides necessary and sufficient conditions for the following two important classes of quantum statistical models; the Holevo bound coincides with the SLD Cramér-Rao bound and it does with the RLD Cramér-Rao bound. One of the important results of this paper is that a general model other than these two special cases exhibits an unexpected property: the structure of the Holevo bound changes smoothly when the weight matrix varies. In particular, it always coincides with the RLD Cramér-Rao bound for a certain choice of the weight matrix. Several examples illustrate these findings.
Bound entanglement and entanglement bounds
Energy Technology Data Exchange (ETDEWEB)
Sauer, Simeon [Physikalisch-Astronomische Fakultaet, Friedrich-Schiller-Univesitaet Jena (Germany)]|[Physikalisches Institut, Albert-Ludwigs-Universitaet Freiburg, Hermann-Herder-Strasse 3, D-79104 Freiburg (Germany); Melo, Fernando de; Mintert, Florian; Buchleitner, Andreas [Physikalisches Institut, Albert-Ludwigs-Universitaet Freiburg, Hermann-Herder-Strasse 3, D-79104 Freiburg (Germany)]|[Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Str.38, D-01187 Dresden (Germany); Bae, Joonwoo [School of Computational Sciences, Korea Institute for Advanced Study, Seoul 130-012 (Korea); Hiesmayr, Beatrix [Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna (Austria)
2008-07-01
We investigate the separability of Bell-diagonal states of two qutrits. By using lower bounds to algebraically estimate concurrence, we find convex regions of bound entangled states. Some of these regions exactly coincide with the obtained results when employing optimal entanglement witnesses, what shows that the lower bound can serve as a precise detector of entanglement. Some hitherto unknown regions of bound entangled states were discovered with this approach, and delimited efficiently.
Lifetime measurement of the low lying yrast states in 189Pt
Chuang-Ye, He; Jin-Long, Wang; Yi-Heng, Wu; Yun, Zheng; Guang-Sheng, Li; Cong-Bo, Li; Shi-Peng, Hu; Hong-Wei, Li; Jia-Jian, Liu; Peng-Wei, Luo; Shun-He, Yao
2013-01-01
Lifetimes of the positive-parity yrast band in 189Pt were measured using the recoil distance Doppler-shift method. A HPGe detector array consisting of 13 detectors was used in conjunction with the plunger device in CIAE. Excited states of 189Pt were populated by the 176Yb (18O, 5n) 189Pt fusion-evaporation reaction at a beam energy 87 MeV. The lifetimes of two levels belonging to the yrast band are measured. The results show that the 17/2+ state in the yrast band has large Qt value, but it deceases quickly with spin increasing. It may be contributed from the shape driving effect of the quasi-neutron from the i13/2 oribital.
Majorana bound state in a coupled quantum-dot hybrid-nanowire system
Deng, M. T.; Vaitiekėnas, S.; Hansen, E. B.; Danon, J.; Leijnse, M.; Flensberg, K.; Nygård, J.; Krogstrup, P.; Marcus, C. M.
2016-12-01
Hybrid nanowires combining semiconductor and superconductor materials appear well suited for the creation, detection, and control of Majorana bound states (MBSs). We demonstrate the emergence of MBSs from coalescing Andreev bound states (ABSs) in a hybrid InAs nanowire with epitaxial Al, using a quantum dot at the end of the nanowire as a spectrometer. Electrostatic gating tuned the nanowire density to a regime of one or a few ABSs. In an applied axial magnetic field, a topological phase emerges in which ABSs move to zero energy and remain there, forming MBSs. We observed hybridization of the MBS with the end-dot bound state, which is in agreement with a numerical model. The ABS/MBS spectra provide parameters that are useful for understanding topological superconductivity in this system.
Short-lived two-soliton bound states in weakly perturbed nonlinear Schrodinger equation.
Dmitriev, Sergey V.; Shigenari, Takeshi
2002-06-01
Resonant soliton collisions in the weakly discrete nonlinear Schrodinger equation are studied numerically. The fractal nature of the soliton scattering, described in our previous works, is investigated in detail. We demonstrate that the fractal scattering pattern is related to the existence of the short-lived two-soliton bound states. The bound state can be regarded as a two-soliton quasiparticle of a new type, different from the breather. We establish that the probability P of a bound state with the lifetime L follows the law P approximately L(-3). In the frame of a simple two-particle model, we derive the nonlinear map, which generates the fractal pattern similar to that observed in the numerical study of soliton collisions. (c) 2002 American Institute of Physics.
Widths of K¯-nuclear deeply bound states in a dynamical model
Mareš, J.; Friedman, E.; Gal, A.
2005-01-01
The relativistic mean field (RMF) model is applied to a system of nucleons and a Kbar meson, interacting via scalar and vector boson fields. The model incorporates the standard RMF phenomenology for bound nucleons and, for the Kbar meson, it relates to low-energy Kbar N and K- atom phenomenology. Deeply bound Kbar nuclear states are generated dynamically across the periodic table and are exhibited for 12C and 16O over a wide range of binding energies. Substantial polarization of the core nucleus is found for these light nuclei. Absorption modes are also included dynamically, considering explicitly both the resulting compressed nuclear density and the reduced phase space for Kbar absorption from deeply bound states. The behavior of the calculated width as function of the Kbar binding energy is studied in order to explore limits on the possible existence of narrow Kbar nuclear states.
Parra-Rivas, Pedro; Gomila, Damia; Colet, Pere; Gelens, Lendert
2017-07-01
Bound states, also called soliton molecules, can form as a result of the interaction between individual solitons. This interaction is mediated through the tails of each soliton that overlap with one another. When such soliton tails have spatial oscillations, locking or pinning between two solitons can occur at fixed distances related with the wavelength of these oscillations, thus forming a bound state. In this work, we study the formation and stability of various types of bound states in the Lugiato-Lefever equation by computing their interaction potential and by analyzing the properties of the oscillatory tails. Moreover, we study the effect of higher order dispersion and noise in the pump intensity on the dynamics of bound states. In doing so, we reveal that perturbations to the Lugiato-Lefever equation that maintain reversibility, such as fourth order dispersion, lead to bound states that tend to separate from one another in time when noise is added. This separation force is determined by the shape of the envelope of the interaction potential, as well as an additional Brownian ratchet effect. In systems with broken reversibility, such as third order dispersion, this ratchet effect continues to push solitons within a bound state apart. However, the force generated by the envelope of the potential is now such that it pushes the solitons towards each other, leading to a null net drift of the solitons. Contribution to the Topical Issue "Theory and Applications of the Lugiato-Lefever Equation", edited by Yanne K. Chembo, Damia Gomila, Mustapha Tlidi, Curtis R. Menyuk.
Institute of Scientific and Technical Information of China (English)
LU Peng-Fei; YAN Lei; YU Zhong-Yuan; GAO Yu-Feng; GAO Tao
2013-01-01
In this paper,potential energy curves for the X1∑+,a3∏,a'3∑+,d3△,A1∏ and I1∑-states of CO have been calculated using complete active space self-consistent field and multi-reference configuration interaction methods.The calculations have been performed at 108 nuclear separations from 0.7 to 4.0 (A) by the aug-cc-PV5Z basis set.Spectroscopic constants for the six low-lying electronic states are found in good agreement with experimental data.The vibrational states of the X1∑+ and A1∏ states are also calculated,which are reliable and accurate by comparison with the experimental data and the other theoretical values.The transition dipole moment (TDM) shows that the TDM of the two states (X1∑+ → A1∏) are reduced strongly with increase of bond length.
Observation of a Novel Low-Lying Excited State in Zinc Complexes.
1985-01-22
Truesdell and G. A. Crosby * Prepared for Publication In The Journal of the American Chemical Society Washington State University Chemical Physics Program...spin signature has not yet been determined. 14 J J- I.F. ...r at.ion/___.. Ielt I, ty Codes Av-*l and/er This work supported in part by the Office of...REFERENCES (I) -Bray, R. G.; Ferguson, J.; Hawkins, C. J. Aust. J. Chem. 1969, 22, 2091. (2) Highland, R. G.; Crosby, G.A. Manuscript In preparation . (3
Bound states of the $\\phi^4$ model via the Non-Perturbative Renormalization Group
Rose, F; Leonard, F; Delamotte, B
2016-01-01
Using the nonperturbative renormalization group, we study the existence of bound states in the symmetry-broken phase of the scalar $\\phi^4$ theory in all dimensions between two and four and as a function of the temperature. The accurate description of the momentum dependence of the two-point function, required to get the spectrum of the theory, is provided by means of the Blaizot--M\\'endez-Galain--Wschebor approximation scheme. We confirm the existence of a bound state in dimension three, with a mass within 1% of previous Monte-Carlo and numerical diagonalization values.
The Relativistic Three-Body Bound State in Three-Dimensions
Directory of Open Access Journals (Sweden)
Hadizadeh M. R.
2016-01-01
Full Text Available Studying of the relativistic three-body bound state in a three-dimensional (3D approach is a necessary first step in a process to eventually perform scattering calculations at GeV energies, where partial-wave expansions are not useful. To this aim we recently studied relativistic effects in the binding energy and for the first time, obtained the relativistic 3B wave function [1]. The relativistic Faddeev integral equations for the bound state are formulated in terms of momentum vectors, and relativistic invariance is incorporated within the framework of Poincaré invariant quantum mechanics.
The Analogue of the Aharonov-Bohm Effect for Bound States for Neutral Particles
Bakke, Knut; Furtado, C.
We study the analogue of the Aharonov-Bohm effect for bound states for a neutral particle with a permanent magnetic dipole moment interacting with an external field. We consider a neutral particle confined to moving between two coaxial cylinders and show the dependence of the energy levels on the Aharonov-Casher quantum flux. Moreover, we show that the same flux dependence of the bound states can be found when the neutral particle is confined to a one-dimensional quantum ring and a quantum dot, and we also calculate the persistent currents in each case.
Lorentz contraction of bound states in 1+1 dimensional gauge theory
Järvinen, M.
2004-09-01
We consider the Lorentz contraction of a fermion-antifermion bound state in 1+1 dimensional QED. In 1+1 dimensions the absence of physical, propagating photons allows us to explicitly solve the weak coupling limit α≪m2 of the Bethe-Salpeter bound state equation in any Lorentz frame. In a time-ordered formalism it is seen that all pair production is suppressed in this limit. The wave function is shown to contract while the mass spectrum is invariant under boosts.
Ikot, A. N.; Obong, H. P.; Abbey, T. M.; Zare, S.; Ghafourian, M.; Hassanabadi, H.
2016-09-01
In this article we use supersymmetry quantum mechanics and factorization methods to study the bound and scattering state of Klein-Gordon equation with deformed Hulthen plus deformed hyperbolical potential for arbitrary state in D-dimensions. The analytic relativistic bound state eigenvalues and the scattering phase factor are found in closed form. We report on the numerical results for the bound state energy in D-dimensions.
Study of hyperfine structure in simple atoms and precision tests of the bound state QED
Energy Technology Data Exchange (ETDEWEB)
Karshenboim, S.G. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany); D.I. Mendeleev Institute for Metrology (VNIIM), St. Petersburg 190005 (Russian Federation); Eidelman, S.I. [Budker Institute for Nuclear Physics and Novosibirsk State University, Novosibirsk, 630090 (Russian Federation); Fendel, P. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany); Ivanov, V.G. [Pulkovo Observatory, St. Petersburg 196140 (Russian Federation); Kolachevsky, N.N. [P.N. Lebedev Physics Institute, Moscow, 119991 (Russian Federation); Shelyuto, V.A. [D.I. Mendeleev Institute for Metrology (VNIIM), St. Petersburg 190005 (Russian Federation); Haensch, T.W. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany)
2006-12-15
We consider the most accurate tests of bound state QED, precision theory of simple atoms, related to the hyperfine splitting in light hydrogen-like atoms. We discuss the HFS interval of the 1s state in muonium and positronium and of the 2s state in hydrogen, deuterium and helium-3 ion. We summarize their QED theory and pay attention to involved effects of strong interactions. We also consider recent optical measurements of the 2s HFS interval in hydrogen and deuterium.
Study of hyperfine structure in simple atoms and precision tests of the bound state QED
Karshenboim, S G; Fendel, P; Ivanov, V G; Kolachevsky, N N; Shelyuto, V A; Hänsch, T W
2006-01-01
We consider the most accurate tests of bound state QED, precision theory of simple atoms, related to the hyperfine splitting in light hydrogen-like atoms. We discuss the HFS interval of the 1s state in muonium and positronium and of the 2s state in hydrogen, deuterium and helium-3 ion. We summarize their QED theory and pay attention to involved effects of strong interactions. We also consider recent optical measurements of the 2s HFS interval in hydrogen and deuterium.
Upper Bounds on the Degeneracy of the Ground State in Quantum Field Models
Directory of Open Access Journals (Sweden)
Asao Arai
2016-01-01
Full Text Available Axiomatic abstract formulations are presented to derive upper bounds on the degeneracy of the ground state in quantum field models including massless ones. In particular, given is a sufficient condition under which the degeneracy of the ground state of the perturbed Hamiltonian is less than or equal to the degeneracy of the ground state of the unperturbed one. Applications of the abstract theory to models in quantum field theory are outlined.
Ground and low-lying excited electronic states of graphene flakes: a density functional theory study
Energy Technology Data Exchange (ETDEWEB)
Tachikawa, Hiroto; Kawabata, Hiroshi, E-mail: hiroto@eng.hokudai.ac.jp [Division of Materials Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628 (Japan)
2011-10-28
Structures and electronic states of graphene flakes (finite and small sized graphenes) have been investigated by means of the density functional theory method. Sizes of graphene flakes examined in this study were n = 7, 10, 14, 19, 29 and 44, where n is the number of benzene rings in the graphene flake. The excitation energies of graphene flakes decreased gradually as a function of the number of the ring (n). The orbitals of the highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) are localized in the edge region of the graphene flake. It was found that the edge region can react with a water molecule and H{sub 2}O is dissociated into OH radical and hydrogen atom (H) without an activation barrier. A lithium ion can bind strongly to the edge region. The ability of the edge region in the graphene flakes was discussed on the basis of theoretical results.
Formation of deeply bound LiRb molecules via photoassociation to near asymptotic states
Lorenz, John D.
We present the results of a spectroscopic study LiRb molecules created via photoassociation (PA) to vibration levels of the 4(1) potential. Atoms are first cooled and trapped in a dual species 7Li/ 85Rb magneto-optical trap (MOT) at temperatures of ≈ 1 mK or less. In a cold sample of sufficient density, PA occurs when a resonant laser field induces a free-bound transition to create molecules in an excited electronic potential. After spontaneous emission the molecules decay to a mixture of free atoms and bound molecules depending on the Franck-Condon factors (FCFs) of the excited and ground state vibrational wavefunctions. While excited LiRb * has been previously detected by trap loss fluorescence detection, ionization spectroscopy is required to determine the population of ground state levels after decay. We detect ground state molecules via resonantly enhanced multiphoton ionization (REMPI) where a two photon ionization transition is enhanced by an intermediate resonance. The intermediate resonances match progressions from the D1pi and possibly B1Π potentials, many of which have known energies obtained from previous heat pipe experiments. This is contrary to the expectation that weakly bound LiRb * should primarily decay to weakly bound levels of the ground state and could point to a possible path for creating molecules in the rovibronic ground state.
Investigation of the $nn\\Lambda$ bound state in pionless effective theory
Ando, Shung-Ichi; Oh, Yongseok
2015-01-01
The possibility of an $nn\\Lambda$ bound state is investigated in the framework of pionless effective field theory at leading order. A system of coupled integral equations are constructed in the spin-isospin basis, of which numerical solutions are investigated. In particular, we make use of the limit cycle behavior, i.e., cyclic singularities of coupled integral equations of the system, which would be associated with the formation of a three-body bound state, so-called the Efimov state, in the unitary limit. Furthermore, we find that, when the sharp momentum cutoff introduced in the integral equations is taken significantly larger than the hard scale of the effective theory, the coupling of a three-body contact interaction becomes cyclically singular indicating the onset of Efimov-like bound state formation. However, the paucity of empirical information to determine the parameters of the theory precludes a definitive conclusion on the existence of such a bound state. As a simple test of the feasibility of the ...
Xing, Wei; Shi, Deheng; Sun, Jinfeng; Zhu, Zunlue
2017-10-01
This paper studied the spectroscopic and transition properties of 36 low-lying states, which came from the first two dissociation limits of B2 molecule. The potential energy curves were calculated with the complete active space self-consistent field (CASSCF) method, which was followed by the internally contracted multireference configuration interaction (icMRCI) plus Davidson modification (icMRCI + Q) approach. Of these 36 states, the 25Σu-, 15Σu+, 25Πu, and 15Δu states were repulsive; the B3Δu, E3Σu+, f1Σu-, g1Πg, 23Πu, 33Σg-, 33Πu, 15Πg, and 33Σu+ states had double wells; the B3Δu, E3Σu+, G3Σu+, f1Σu-, g1Πg, 33Σg-, 23Πu, 33Πu, 15Πg, 25Πg, 25Σg-, and 33Σu+ states had one barrier; the 25Σg- state and the second wells of B3Δu, E3Σu+, 15Πg, f1Σu-, g1Πg, and 23Πu states were weakly bound; and the 25Σg- state had no vibrational levels. The avoided crossings existed between the B3Δu and 23Δu states, the E3Σu+ and G3Σu+ states, the G3Σu+ and 33Σu+ states, the 33Σu+ and 43Σu+ states, the 23Πu and 33Πu states, the g1Πg and 21Πg states, the 23Σg- and 33Σg- states, the 15Πg and 25Πg states, the 25Πg and 35Πg states, the 25Σg- and 35Σg- states, as well as the F3Πg and 33Πg states. Core-valence correlation and scalar relativistic corrections were taken into account. The extrapolation to the complete basis set limit was done. The spectroscopic parameters and vibrational properties were obtained. The transition dipole moments were calculated. Franck-Condon factors of some transitions were evaluated. The spin-orbit coupling (SOC) effect on the spectroscopic parameters and vibrational properties is tiny and sometimes even can be negligible. The results determined in this paper can provide some powerful guidelines to observe these states, in particular the states which have not been studied in the experiment.
Directory of Open Access Journals (Sweden)
C. Romig
2015-05-01
Full Text Available The technique of self absorption has been applied for the first time to study the decay pattern of low-lying dipole states of 140Ce. In particular, ground-state transition widths Γ0 and branching ratios Γ0Γ to the ground state have been investigated in the energy domain of the pygmy dipole resonance. Relative self-absorption measurements allow for a model-independent determination of Γ0. Without the need to perform a full spectroscopy of all decay channels, also the branching ratio to the ground state can be determined. The experiment on 140Ce was conducted at the bremsstrahlung facility of the superconducting Darmstadt electron linear accelerator S-DALINAC. In total, the self-absorption and, thus, Γ0 were determined for 104 excited states of 140Ce. The obtained results are presented and discussed with respect to simulations of γ cascades using the DICEBOX code.
Manipulation of Squeezed Two-Phonon Bound States using Femtosecond Laser Pulses
Directory of Open Access Journals (Sweden)
Nakamura Kazutaka G.
2013-03-01
Full Text Available Two-phonon bound states have been excited exclusively in ZnTe(110 via impulsive stimulated second-order Raman scattering, essentially being squeezed states due to phase coherent excitation of two identical components anticorrelated in the wave vector. By using coherent control technique with a pair of femtosecond laser pulses, the manipulation of squeezed states has been demonstrated in which both the amplitude and lifetime of coherent oscillations of squeezed states are modulated, indicating the feasibility to control the quantum noise and the quantum nature of phonon squeezed states, respectively.
Aspects of Majorana Bound States in One-Dimensional Systems with and without Time-Reversal Symmetry
DEFF Research Database (Denmark)
Wölms, Konrad Udo Hannes
bound states in the measurement still has to be understood better. And example would be the frequently performed tunnel probe measurement on Majorana bound states [26, 40, 41]. A second reason why Majorana bound states are interesting is their potential application to a certain quantum computation...... scheme. This scheme, called topological quantum computation, relies on the braiding of so-called non-abelian anyons in order to perform computations [18]. Majorana bound states are the simplest example of such non-abelian anyons. No other non-abelian anyons have been realized experimentally yet, which...... puts further focus on the study of Majorana bound states. Additionally to probing Majorana bound states, their use in topological quantum computation also requires them to be manipulated. This also poses an interesting problem for both experimentalists and theorists [25, 27]. We can summarize...
Resonances from QCD bound states and the 750 GeV diphoton excess
Kats, Yevgeny; Strassler, Matthew J.
2016-05-01
Pair production of colored particles is in general accompanied by production of QCD bound states (onia) slightly below the pair-production threshold. Bound state annihilation leads to resonant signals, which in some cases are easier to see than the decays of the pair-produced constituents. In a previous paper ( arXiv:1204.1119 URL"/> ) we estimated the bound state signals, at leading order and in the Coulomb approximation, for particles with various spins, color representations and electric charges, and used 7 TeV ATLAS and CMS resonance searches to set rough limits. Here we update our results to include 8 and 13 TeV data. We find that the recently reported diphoton excesses near 750 GeV could indeed be due to a bound state of this kind. A narrow resonance of the correct size could be obtained for a color-triplet scalar with electric charge -4/3 and mass near 375GeV, if (as a recent lattice computation suggests) the wave function at the origin is somewhat larger than anticipated. Pair production of this particle could have evaded detection up to now. Other candidates may include a triplet scalar of charge 5/3, a triplet fermion of charge -4/3, and perhaps a sextet scalar of charge -2/3.
On the energy of bound states for magnetic Schrödinger operators
DEFF Research Database (Denmark)
Fournais, Søren; Kachmar, Ayman
2009-01-01
We provide a leading order semiclassical asymptotics of the energy of bound states for magnetic Neumann Schrödinger operators in two-dimensional (exterior) domains with smooth boundaries. The asymptotics is valid all the way up to the bottom of the essential spectrum. When the spectral parameter...
Bound state transfer matrix for AdS5 × S5 superstring
Arutyunov, G.E.; de Leeuw, M.; Suzuki, R.; Torrielli, A.
2009-01-01
We apply the algebraic Bethe ansatz technique to compute the eigenvalues of the transfer matrix constructed from the general bound state S-matrix of the light-cone AdS5 × S5 superstring. This allows us to verify certain conjectures on the quantum characteristic function, and to extend them to the ge
Bound states of the Dirac equation with some physical potentials by the Nikiforov-Uvarov method
Energy Technology Data Exchange (ETDEWEB)
Setare, Mohammad R; Haidari, S [Department of Physics, University of Kurdistan, Pasdaran Avenue, Sanandaj (Iran, Islamic Republic of)], E-mail: rezakord@ipm.ir, E-mail: heidary.somayeh@gmail.com
2010-01-15
Exact analytical solutions for the s-wave Dirac equation with the reflectionless-type, Rosen-Morse and Manning-Rosen potentials are obtained, under the condition of spin symmetry. We obtained bound state energy eigenvalues and corresponding spinor wave function in the framework of the Nikiforov-Uvarov (NU) method.
Light Fermion Finite Mass Effects in Non-relativistic Bound States
Eiras, D; Eiras, Dolors; Soto, Joan
2000-01-01
We present analytic expressions for the vacuum polarization effects due to a light fermion with finite mass in the binding energy and in the wave function at the origin of QED and (weak coupling) QCD non-relativistic bound states. Applications to exotic atoms, \\Upsilon (1s) and t\\bar{t} production near threshold are briefly discussed.
Applying the relativistic quantization condition to a three-particle bound state in a periodic box
Hansen, Maxwell T
2016-01-01
Using our recently developed relativistic three-particle quantization condition, we study the finite-volume energy shift of a three-particle bound state. We reproduce the result obtained using non-relativistic quantum mechanics by Mei{\\ss}ner, R{\\'i}os and Rusetsky, and generalize the result to a moving frame.
The Need for an Upward Bound Project at Bowie State College.
Gill, Wanda E.
Reasons that Bowie State College in Maryland should participate in the Upward Bound Project are discussed, with attention to geographic and demographic characteristics of the area, school characteristics, and needed services. The college historically has provided educational opportunities for black, disadvantaged students and has been successful…
Liu, H; Glöckle, W; Elster, Ch.
2002-01-01
The Faddeev equations for the three-body bound state are solved directly as thre e-dimensional integral equations without employing partial wave decomposition. Two-body forces of the Malfliet-Tjon type and simple spin independent genuine three-body forces are considered for the calculation of the three-body binding energy.
Bakke, K.
2010-10-01
We obtain the solutions of the Dirac equation when the noninertial effects of the Fermi-Walker reference frame break the relativistic Landau-Aharonov-Casher quantization, but they provide bound states in an analogous way to a Dirac neutral particle subject to Tan-Inkson quantum dot potential [W.-C. Tan, J.C. Inkson, Semicond. Sci. Technol. 11 (1996) 1635].
Exact solutions of the spinor Bethe-Salpeter equation for tightly bound states
Suttorp, L.G.
1975-01-01
Exact solutions are obtained for the spinor Bethe-Salpeter equation that describes tightly bound states of spin-/sup 1///sub 2/ fermions with massless-boson exchange. The corresponding coupling constants form a discrete spectrum that depends continuously on the parameters characterizing the type of
The Bound State S-matrix of the Deformed Hubbard Chain
de Leeuw, Marius; Matsumoto, Takuya
2011-01-01
In this work we use the q-oscillator formalism to construct the atypical (short) supersymmetric representations of the centrally extended Uq (su(2|2)) algebra. We then determine the S-matrix describing the scattering of arbitrary bound states. The crucial ingredient in this derivation is the affine extension of the aforementioned algebra.
Exact solutions of the spinor Bethe-Salpeter equation for tightly bound states
Suttorp, L.G.
1975-01-01
Exact solutions are obtained for the spinor Bethe-Salpeter equation that describes tightly bound states of spin-/sup 1///sub 2/ fermions with massless-boson exchange. The corresponding coupling constants form a discrete spectrum that depends continuously on the parameters characterizing the type of
Bound State Solutions of Klein-Gordon Equation with the Kratzer Potential
Institute of Scientific and Technical Information of China (English)
M. Ko(c)ak
2007-01-01
The relativistic problem of spinless particle subject to a Kratzer potential is analysed. Bound state solutions for s-waves are found by separating the Klein-Gordon equation into two parts. Unlike the similar works in the literature, the separation make it possible to see explicitly the relativistic contributions, if any, to the solution in the non-relativistic limit.
Precision study of positronium and precision tests of the bound state QED
Karshenboim, Savely G.
2002-01-01
Despite its very short lifetime positronium provides us with a number of accurate tests of the bound state QED. In this note a brief overview of QED theory and precision experiments on the spectrum and annihilation decay of the positronium atom is presented. Special attention is paid to the accuracy of theoretical predictions.
Resonances from QCD bound states and the 750 GeV diphoton excess
Kats, Yevgeny
2016-01-01
Pair production of colored particles is in general accompanied by production of QCD bound states (onia) slightly below the pair-production threshold. Bound state annihilation leads to resonant signals, which in some cases are easier to see than the decays of the pair-produced constituents. In a previous paper (arXiv:1204.1119) we estimated the bound state signals, at leading order and in the Coulomb approximation, for particles with various spins, color representations and electric charges, and used 7 TeV ATLAS and CMS resonance searches to set rough limits. Here we update our results to include 8 and 13 TeV data. We find that the recently reported diphoton excesses near 750 GeV could indeed be due to a bound state of this kind. A narrow resonance of the correct size could be obtained for a color-triplet scalar with electric charge -4/3 and mass near 375 GeV, if (as a recent lattice computation suggests) the wave function at the origin is somewhat larger than anticipated. Pair production of this particle coul...
Onyeaju, M. C.; Ikot, A. N.; Chukwuocha, E. O.; Obong, H. P.; Zare, S.; Hassanabadi, H.
2016-09-01
Scattering and bound states solution for the one-dimensional Klein-Gordon particle with Hylleraas potential is presented within the frame work of position dependent effective mass formalism. We calculate in detail the reflection and transmission coefficients using the properties of hypergeometric functions and the equation of continuity of the wave functions.
Bound States of the S-Wave Equation with Equal Scalar and Vector Standard Eckart Potential
Institute of Scientific and Technical Information of China (English)
Eser Ol(g)ar; Ramazan Ko(c); Hayriye Tütüncüler
2006-01-01
@@ A supersymmetric technique for the bound-state solutions of the s-wave Klein-Gordon equation with equal scalar and vector standard Eckart-type potential is proposed. Its exact solutions are obtained. Possible generalization of our approach is outlined.
Spin(p+1, p+1) covariant Dp-brane bound states
Sundell, P
2001-01-01
We construct Spin(p + 1, p + 1) covariant Dp-brane bound states by using the fact that the potentials in the RR sector of toroidically compactified type Ii supergravity transform as a chiral spinor of the T duality group. As an application, we show the invariance of the zero-force condition for a pr
Charmed mesic nuclei Bound D and over D states with 208Pb
Tsushima, K; Thomas, A W; Saitô, K; Landau, Rubin H
1999-01-01
We show that the $D^-$ meson will inevitably form narrow bound states with $^{208}$Pb. The experimental confirmation and comparison with the $\\bar{D}^0$ and $D^0$ will provide distinctive information on the nature of the interaction between the charmed meson and matter.
ηN interactions in the nuclear medium. η-nuclear bound states
Mareš, J.; Barnea, N.; Cieplý, A.; Friedman, E.; Gal, A.
2016-11-01
We report on our recent study of in-medium ηN interactions and η-nuclear quasi-bound states. The ηN scattering amplitudes considered in the calculations are constructed within coupled-channel models that incorporate the S11 N*(1535) resonance. The implications of self-consistent treatment and the role played by subthreshold dynamics are discussed.
A new interpretation of the proton-neutron bound state The calculation of the binding energy
Mandache, N
1996-01-01
We treat the old problem of the proton-neutron bound state (the deuteron). Using a new concept of incomplete (partial) annihilation process we derive a formula for the binding energy of the deuteron, which does not contain any new constant. Some implications of this new approach are discussed.
Quasi bound states in the continuum with few unit cells of photonic crystal slab
DEFF Research Database (Denmark)
Taghizadeh, Alireza; Chung, Il-Sug
2017-01-01
Bound states in the continuum (BICs) in photonic crystal slabs represent the resonances with an infinite quality (Q)-factor, occurring above the light line for an infinitely periodic structure. We show that a set of BICs can turn into quasi-BICs with a very high Q-factor even for two or three unit...
WKB formalism and a lower limit for the energy eigenstates of bound states for some potentials
Barragan-Gil, L F; Barragan-Gil, Luis F.; Camacho, Abel
2007-01-01
In the present work the conditions appearing in the WKB approximation formalism of quantum mechanics are analyzed. It is shown that, in general, a careful definition of an approximation method requires the introduction of two length parameters, one of them always considered in the text books on quantum mechanics, whereas the second one is usually neglected. Afterwards we define a particular family of potentials and prove, resorting to the aforementioned length parameters, that we may find an energy which is a lower bound to the ground energy of the system. The idea is applied to the case of a harmonic oscillator and also to a particle freely falling in a homogeneous gravitational field, and in both cases the consistency of our method is corroborated. This approach, together with the Rayleigh--Ritz formalism, allows us to define an energy interval in which the ground energy of any potential, belonging to our family, must lie.
Study of the γ decay of high-lying states in 208Pb via inelastic scattering of 17O ions
Directory of Open Access Journals (Sweden)
Crespi F.C.L.
2012-12-01
Full Text Available High-lying states in 208Pb nucleus were populated via inelastic scattering of a 17O beam at bombarding energy of 20 MeV/u. Their subsequent gamma decay was measured with the detector system AGATA Demonstrator based on HPGe detectors, coupled to an array of large volume LaBr3:Ce scintillators. Preliminary results in comparison with (γ,γ′ data, for states in the 5–8 MeV energy interval, seem to indicate that in that region the states belong to two different groups one with a isoscalar character and the other with a isovector nature. This is similar to what was observed in other stable nuclei with (α,α′γ experiments. The multipolarity of the observed gamma transitions is determined with remarkable sensitivity thanks to angular distribution measurements. Data aiming at studying the neutron decay of the Giant Quadrupole Resonance in the 208Pb by the high resolution measurement of the following gamma decay are also presented in their preliminary form.
Quasiparticle parity lifetime of bound states in a hybrid superconductor-semiconductor quantum dot
Higginbotham, Andrew; Albrecht, Sven; Kirsanskas, Gediminas; Chang, Willy; Kuemmeth, Ferdinand; Krogstrup, Peter; Jespersen, Thomas; Nygård, Jesper; Flensberg, Karsten; Marcus, Charles
2015-03-01
We measure quasiparticle transport in an InAs nanowire that is half-covered with epitaxial superconducting aluminum, then locally gated to form a quantum dot. We observe negative differential conductance at finite source-drain bias, and temperature dependent even-odd alternations in the Coulomb blockade peak spacings at zero bias. These observations can be understood in terms of a mid-gap semiconductor discrete state and a continuum of BCS quasiparticle states. Comparing with simple models, we bound the discrete state's parity lifetime and the quasiparticle temperature. These results indicate that parity fluctuations are slow, and imply Majorana qubit poisoning times on the order of a millisecond. Additional results indicate that the bound states move to zero energy in a magnetic field, qualitatively consistent with expectations for Majorana fermions in a finite system. Research supported by Microsoft Station Q, Danish National Research Foundation, Villum Foundation, Lundbeck Foundation, and the European Commission.
Gate-tunable Andreev bound states in InSb nanowire Josephson junction
Energy Technology Data Exchange (ETDEWEB)
Kang, Ning; Li, Sen; Fan, Dingxun; Xu, Hongqi [Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871 (China); Caroff, Philippe [Division of Solid State Physics, Lund University, P. O. Box 118, S-221 00 Lund (Sweden)
2016-07-01
Hybrid InSb nanowire-superconductor devices are promising candidates for investigating Majorana modes in solid-state devices and future technologies of topological quantum manipulation. Here, we report low-temperature transport measurements on an individual InSb nanowire quantum dot coupled to superconducting contacts that exhibit an interplay between the Kondo effects and superconductivity. We observed two types of subgap resonance states within the superconducting gap, which can be attributed to gate-tunable Andreev bound states in Coulomb valleys with different Kondo temperatures. The presence of the gate-tunable 0 and pi junction allow us to investigate the fundamental 0- pi transition. Detailed magnetic field and temperature evolution of level spectroscopy demonstrate different behavior of two types of the Andreev bound states. Our results exhibit that the InSb nanowires can provide a promising platform for exploring phase coherence transport and the effect of spin-orbit coupling in semiconductor nanowire-superconductor hybrid device.
Bounds on probability of state transfer with respect to readout time and edge weight
Gordon, Whitney; Kirkland, Steve; Li, Chi-Kwong; Plosker, Sarah; Zhang, Xiaohong
2016-02-01
We analyze the sensitivity of a spin chain modeled by an undirected weighted connected graph exhibiting perfect state transfer to small perturbations in readout time and edge weight in order to obtain physically relevant bounds on the probability of state transfer. At the heart of our analysis is the concept of the numerical range of a matrix; our analysis of edge weight errors additionally makes use of the spectral and Frobenius norms.
Reflection algebra, Yangian symmetry and bound-states in AdS/CFT
MacKay, Niall
2011-01-01
We present the `Heisenberg picture' of the reflection algebra by explicitly constructing the boundary Yangian symmetry of the AdS/CFT superstring ending on a boundary with degrees of freedom and preserving all of the bulk symmetry algebra. This enables us to present the bound-state reflection matrices in a more elegant, rapidity-difference form. We also consider the spectrum of bulk and boundary states and some automorphisms of the underlying algebras.
Scattering resonances and two-particle bound states of the extended Hubbard model
Energy Technology Data Exchange (ETDEWEB)
Valiente, M; Petrosyan, D [Institute of Electronic Structure and Laser, FORTH, 71110 Heraklion, Crete (Greece)
2009-06-28
We present a complete derivation of two-particle states of the one-dimensional extended Bose-Hubbard model involving attractive or repulsive on-site and nearest-neighbour interactions. We find that this system possesses scattering resonances and two families of energy-dependent interaction-bound states which are not present in the Hubbard model with the on-site interaction alone. (fast track communication)
Reduced adiabatic hyperspherical basis in the Coulomb three-body bound state problem
Energy Technology Data Exchange (ETDEWEB)
Abramov, D.I. [Sankt Peterburgskij Univ., St. Petersburg (Russian Federation); Gusev, V.V. [Institut Fiziki Vysokikh Ehnergij, Protvino (Russian Federation); Ponomarev, L.I. [Rossijskij Nauchnyj Tsentr ``Kurchatovskij Inst.``, Moscow (Russian Federation)
1996-10-01
A new version of the adiabatic hyperspherical approach (AHSA) is suggested which has significant advantages for the calculation of three-body states with total angular momentum J > 0. The binding energies of all bound states of mesic molecules with normal parity are calculated by the suggested method. Comparison with results of variational calculations and the fast convergence of the method confirm its high efficiency. (orig.). 13 refs.
Delayed birth of distillable entanglement in the evolution of bound entangled states
Derkacz, Łukasz
2010-01-01
The dynamical creation of entanglement between three-level atoms coupled to the common vacuum is investigated. For the class of bound entangled initial states we show that the dynamics of closely separated atoms generates stationary distillable entanglement of asymptotic states. We also find that the effect of delayed sudden birth of distillable entanglement occurs in the case of atoms separated by a distance comparable with the radiation wavelength.
Tight bound on coherent-state-based entanglement generation over lossy channels
Azuma, Koji; Koashi, Masato; Imoto, Nobuyuki
2009-01-01
The first stage of the hybrid quantum repeaters is entanglement generation based on transmission of pulses in coherent states over a lossy channel. Protocols to make entanglement with only one type of error are favorable for rendering subsequent entanglement distillation efficient. Here we provide the tight upper bound on performances of these protocols that is determined only by the channel loss. In addition, we show that this bound is achievable by utilizing a proposed protocol [arXiv:0811.3100] composed of a simple combination of linear optical elements and photon-number-resolving detectors.
Rovibrational bound states of SO{sub 2} isotopologues. I: Total angular momentum J = 0–10
Energy Technology Data Exchange (ETDEWEB)
Kumar, Praveen, E-mail: Praveen.Kumar@ttu.edu; Ellis, Joseph; Poirier, Bill, E-mail: Bill.Poirier@ttu.edu
2015-04-01
Highlights: • We report calculation of the exact rovibrational energy levels of SO{sub 2} for J = 0–10. • We report sulfur isotope shifts of the SO{sub 2} isotopologues rovibrational frequencies. • Coriolis coupling is treated exactly. • All rovibrational levels are computed to a high level of numerical convergence. • All of the rovibrational data exhibit near-perfect mass-dependent fractionation. - Abstract: Isotopic variation of the rovibrational bound states of SO{sub 2} for the four stable sulfur isotopes {sup 32–34,36}S is investigated in comprehensive detail. In a two-part series, we compute the low-lying energy levels for all values of total angular momentum in the range J = 0–20. All rovibrational levels are computed, to an extremely high level of numerical convergence. The calculations have been carried out using the ScalIT suite of parallel codes. The present study (Paper I) examines the J = 0–10 rovibrational levels, providing unambiguous symmetry and rovibrational label assignments for each computed state. The calculated vibrational energy levels exhibit very good agreement with previously reported experimental and theoretical data. Rovibrational energy levels, calculated without any Coriolis approximations, are reported here for the first time. Among other potential ramifications, this data will facilitate understanding of the origin of mass-independent fractionation of sulfur isotopes in the Archean rock record—of great relevance for understanding the “oxygen revolution”.
Bound states of massive fermions in Aharonov-Bohm-like fields
Energy Technology Data Exchange (ETDEWEB)
Khalilov, V.R. [Moscow State University, Faculty of Physics, Moscow (Russian Federation)
2014-01-15
Bound states of massive fermions in Aharonov-Bohm (AB)-like fields have analytically been studied. The Hamiltonians with the (AB)-like potentials are essentially singular and therefore require specification of a one-parameter self-adjoint extension. We construct self-adjoint Dirac Hamiltonians with the AB potential in 2+1 dimensions that are specified by boundary conditions at the origin. It is of interest that for some range of the extension parameter the AB potential can bind relativistic charged massive fermions. The bound-state energy is determined by the AB magnetic flux and depends upon the fermion spin and extension parameter; it is a periodical function of the magnetic flux. We also construct self-adjoint Hamiltonians for the so-called Aharonov-Casher (AC) problem, show that nonrelativistic neutral massive fermions can be bound by the (AC) background, determine the range of the extension parameter in which fermion bound states exist, and find their energies as well as wave functions. (orig.)
Lower bounds for ballistic current and noise in non-equilibrium quantum steady states
Directory of Open Access Journals (Sweden)
Benjamin Doyon
2015-03-01
Full Text Available Let an infinite, homogeneous, many-body quantum system be unitarily evolved for a long time from a state where two halves are independently thermalized. One says that a non-equilibrium steady state emerges if there are nonzero steady currents in the central region. In particular, their presence is a signature of ballistic transport. We analyze the consequences of the current observable being a conserved density; near equilibrium this is known to give rise to linear wave propagation and a nonzero Drude peak. Using the Lieb–Robinson bound, we derive, under a certain regularity condition, a lower bound for the non-equilibrium steady-state current determined by equilibrium averages. This shows and quantifies the presence of ballistic transport far from equilibrium. The inequality suggests the definition of “nonlinear sound velocities”, which specialize to the sound velocity near equilibrium in non-integrable models, and “generalized sound velocities”, which encode generalized Gibbs thermalization in integrable models. These are bounded by the Lieb–Robinson velocity. The inequality also gives rise to a bound on the energy current noise in the case of pure energy transport. We show that the inequality is satisfied in many models where exact results are available, and that it is saturated at one-dimensional criticality.
Lower bounds for the ground-state degeneracies of frustrated systems on fractal lattices
Curado; Nobre
2000-12-01
The total number of ground states for nearest-neighbor-interaction Ising systems with frustrations, defined on hierarchical lattices, is investigated. A simple method is presented, which allows one to factorize the ground-state degeneracy, at a given hierarchy level n, in terms of contributions due to all hierarchy levels. Such a method may yield the exact ground-state degeneracy of uniformly frustrated systems, whereas it works as an approximation for randomly frustrated models. In the latter cases, it is demonstrated that such an approximation yields lower-bound estimates for the ground-state degeneracies.
Ionization and bound-state relativistic quantum dynamics in laser-driven multiply charged ions
Energy Technology Data Exchange (ETDEWEB)
Hetzheim, Henrik
2009-01-14
The interaction of ultra-strong laser fields with multiply charged hydrogen-like ions can be distinguished in an ionization and a bound dynamics regime. Both are investigated by means of numerically solving the Dirac equation in two dimensions and by a classical relativistic Monte-Carlo simulation. For a better understanding of highly nonlinear physical processes the development of a well characterized ultra-intense relativistic laser field strength has been driven forward, capable of studying e.g. the magnetic field effects of the laser resulting in an additional electron motion in the laser propagation direction. A novel method to sensitively measure these ultra-strong laser intensities is developed and employed from the optical via the UV towards the XUV frequency regime. In the bound dynamics field, the determination of multiphoton transition matrixelements has been investigated between different bound states via Rabi oscillations. (orig.)
Ghost-gluon and ghost-quark bound states and their role in BRST quartets
Alkofer, Natalia
2011-01-01
A non-perturbative version of the BRST quartet mechanism in infrared Landau gauge QCD is proposed for transverse gluons and quarks. Based on the positivity violation for transverse gluons the content of the respective non-perturbative BRST quartet is derived. To identify the gluon's BRST-daughter and second parent state, a truncated Bethe-Salpeter equation for the gluon-(anti-)ghost bound state is investigated. We comment shortly on several equivalent forms of this equation. Repeating the same construction for quarks leads to a truncated Bethe-Salpeter equation for a fundamentally charged quark-(anti-)ghost bound state. It turns out that a cardinal input to this equation is given by the fully dressed quark-gluon vertex, and that it is indispensable to dress the quark-gluon vertex in this equation in order to obtain a consistent truncation.
Three-body bound states with zero-range interaction in the Bethe-Salpeter approach
Ydrefors, E.; Alvarenga Nogueira, J. H.; Gigante, V.; Frederico, T.; Karmanov, V. A.
2017-07-01
The Bethe-Salpeter equation for three bosons with zero-range interaction is solved for the first time. For comparison the light-front equation is also solved. The input is the two-body scattering length and the outputs are the three-body binding energies, Bethe-Salpeter amplitudes and light-front wave functions. Three different regimes are analyzed: (i) For weak enough two-body interaction the three-body system is unbound. (ii) For stronger two-body interaction a three-body bound state appears. It provides an interesting example of a deeply bound Borromean system. (iii) For even stronger two-body interaction this state becomes unphysical with a negative mass squared. However, another physical (excited) state appears, found previously in light-front calculations. The Bethe-Salpeter approach implicitly incorporates three-body forces of relativistic origin, which are attractive and increase the binding energy.
Effect of bound-state dressing in laser-assisted radiative recombination
Müller, Robert A.; Seipt, Daniel; Fritzsche, Stephan; Surzhykov, Andrey
2015-11-01
We present a theoretical study on the recombination of a free electron into the ground state of a hydrogenlike ion in the presence of an external laser field. Emphasis is placed on the effects caused by the laser dressing of the residual ionic bound state. To investigate how this dressing affects the total and angle-differential cross section of laser-assisted radiative recombination (LARR) we apply first-order perturbation theory and the separable Coulomb-Volkov continuum ansatz. Using this approach, detailed calculations are performed for low-Z hydrogenlike ions and laser intensities in the range from IL=1012 to 1013W/cm2 . It is seen that the total cross section as a function of the laser intensity is remarkably affected by the bound-state dressing. Moreover, the laser dressing becomes manifest as asymmetries in the angular distribution and the (energy) spectrum of the emitted recombination photons.
Impact of electron–vibron interaction on the bound states in the continuum
Energy Technology Data Exchange (ETDEWEB)
Álvarez, C. [GISC, Departamento de Física de Materiales, Universidad Complutense, E-28040 Madrid (Spain); Domínguez-Adame, F., E-mail: adame@fis.ucm.es [GISC, Departamento de Física de Materiales, Universidad Complutense, E-28040 Madrid (Spain); Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Orellana, P.A. [Departamento de Física, Universidad Técnica Federico Santa María, Casilla 110 V, Valparaíso (Chile); Díaz, E. [GISC, Departamento de Física de Materiales, Universidad Complutense, E-28040 Madrid (Spain)
2015-06-12
We investigate the nonequilibrium transport properties of a coupled quantum dot system connected in parallel to two leads, including electron–vibron interaction. It is known that in the absence of interaction the system supports a bound state in the continuum. This state is revealed as a Fano antiresonance in the transmission when the energy levels of the dots are detuned. Using the Keldysh nonequilibrium Green's function formalism, we find that the occurrence of the Fano antiresonance arises even if the electron–vibration interaction is taken into account. We also examine the impact of the coupling to the leads in the linear response of the system. We conclude that the existence of bound states in the continuum in coupled quantum dot systems is a robust phenomenon, opening the possibility of its observation in experiments.
Harston, M R; Chemin, J F; Karpeshin, F; Trzhaskovskaya, M B
2000-01-01
Theoretical results are presented for rate of decay of the 3/2+ isomeric nuclear state of sup 1 sup 2 sup 5 Te by excitation of atomic electrons to bound states in the ions Te sup 4 sup 5 sup + and Te sup 4 sup 6 sup +. In these ions the nuclear transition energy lies just below the threshold for emission of a K-shell electron to the continuum with the result that normal K-shell internal conversion is energetically forbidden. However recent experimental results indicate that excitation of K-shell electrons is still significant in these ions. The theoretical results presented here for internal conversion to bound final states are in quantitative agreement with experiment and thereby confirm the contribution of near-resonant electron-nucleus transitions involving a bound final state.
An Ab Initio Study of the Low-Lying Doublet States of AgO and AgS
Bauschlicher, Charles W., Jr.; Partridge, Harry; Langhoff, Stephen R.
1990-01-01
Spectroscopic constants (D(sub o), r(sub e), mu(sub e), T(sub e)) are determined for the doublet states of AgO and AgS below approx. = 30000/cm. Large valence basis sets are employed in conjunction with relativistic effective core potentials (RECPs). Electron correlation is included using the modified coupled-pair functional (MCPF) and multireference configuration interaction (MRCI) methods. The A(sup 2)Sigma(sup +) - X(sup 2)Pi band system is found to occur in the near infrared (approx. = 9000/cm) and to be relatively weak with a radiative lifetime of 900 microns for A(sup 2)Sigma(sup +) (upsilon = 0). The weakly bound C(sup 2)Pi state (our notation), the upper state of the blue system, is found to require high levels of theoretical treatment to determine a quantitatively accurate potential. The red system is assigned as a transition from the C(sup 2)Pi state to the previously unobserved A(sup 2)Sigma(sup +) state. Several additional transitions are identified that should be detectable experimentally. A more limited study is performed for the vertical excitation spectrum of AgS. In addition, a detailed all-electron study of the X(sup 2)Pi and A(sup 2)Sigma(sup +) states of AgO is carried out using large atomic natural orbital (ANO) basis sets. Our best calculated D(sub o) value for AgO is significantly less than the experimental value, which suggests that there may be some systematic error in the experimental determination.
Afzal, Muhammad Imran; Lee, Yong Tak
2016-01-01
Von Neumann and Wigner theorized bounding of asymmetric eigenstates and anti-crossing of symmetric eigenstates. Experiments have shown that owing to anti-crossing and similar radiation rates, graphene-like resonance of inhomogeneously strained photonic eigenstates can generate pseudomagnetic field, bandgaps and Landau levels, while dissimilar rates induce non-Hermicity. Here, we showed experimentally higher-order supersymmetry and quantum phase transitions by resonance between similar one dimensional lattices. The lattices consisted of inhomgeneously strain-like phases of triangular solitons. The resonance created two dimensional inhomogeneously deformed photonic graphene. All parent eigenstates are annihilated. Where eigenstates of mildly strained solitons are annihilated with similar (power law) rates through one tail only and generated Hermitianally bounded eigenstates. The strongly strained solitons, positive defects are annihilated exponentially through both tails with dissimilar rates. Which bounded eig...
The double radiative annihilation of the heavy-light fermion bound states
Eeg, Jan O; Picek, I
2001-01-01
We consider the double-radiative decays of heavy-light QED and QCD atoms, $\\mu^+ e^- \\to \\gamma\\gamma$ and $\\bar{B}^{0}_s \\to \\gamma\\gamma$. Especially, we take under scrutiny contributions coming from operators that vanish on the free-quark mass shell. We show that by field redefinitions these operators are converted into contact terms attached to the bound state dynamics. A net off-shell contribution is suppressed with respect to the effect of the well known flavour-changing magnetic-moment operator by the bound-state binding factor. The negligible off-shellness of the weakly bound QED atoms becomes more relevant for strongly bound QCD atoms. We analyze this off-shellness in model-approaches to QCD, one of them enabling us to keep close contact to the related effect in QED. We also comment on the off-shell effect in the corresponding process $\\bar{B}_d \\to K^* \\gamma$, and discuss possible hindering of the claimed beyond-standard-model discovery in this decay mode.
A Density Matrix Renormalization Group Approach to an Asymptotically Free Model with Bound States
Martín-Delgado, M A
1999-01-01
We apply the DMRG method to the 2 dimensional delta function potential which is a simple quantum mechanical model with asymptotic freedom and formation of bound states. The system block and the environment block of the DMRG contain the low energy and high energy degrees of freedom, respectively. The ground state energy and the lowest excited states are obtained with an unprecedent accuracy. We compare the DMRG method with the Similarity RG method and propose its generalization to field theoretical models in high energy physics.
Spectrum of Andreev bound states in Josephson junctions with a ferromagnetic insulator
Energy Technology Data Exchange (ETDEWEB)
Kawabata, Shiro, E-mail: s-kawabata@aist.go.jp [Nanosystem Research Institute (NRI), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); CREST, Japan Science and Technology Corporation (JST), Kawaguchi, Saitama 332-0012 (Japan); Tanaka, Yukio [Department of Applied Physics, Nagoya University, Nagoya 464-8603 (Japan); Golubov, Alexander A. [Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands); Vasenko, Andrey S. [Institut Laue-Langevin, 6 rue Jules Horowitz, BP 156, 38042 Grenoble (France); Asano, Yasuhiro [Department of Applied Physics, Hokkaido University, Sapporo 060-8628 (Japan)
2012-10-15
Ferromagnetic-insulator (FI) based Josephson junctions are promising candidates for a coherent superconducting quantum bit as well as a classical superconducting logic circuit. Recently the appearance of an intriguing atomic-scale 0-{pi} transition has been theoretically predicted. In order to uncover the mechanism of this phenomena, we numerically calculate the spectrum of Andreev bound states in a FI barrier by diagonalizing the Bogoliubov-de Gennes equation. We show that Andreev spectrum drastically depends on the parity of the FI-layer number L and accordingly the {pi}(0) state is always more stable than the 0 ({pi}) state if L is odd (even).
Two qubits of a W state violate Bell's inequality beyond Cirel'son's bound
Cabello, A
2002-01-01
It is shown that the correlations between two qubits selected from a trio prepared in a W state violate the Clauser-Horne-Shimony-Holt inequality more than the correlations between two qubits in any quantum state. Such a violation beyond Cirel'son's bound is smaller than the one achieved by two qubits selected from a trio in a Greenberger-Horne-Zeilinger state [A. Cabello, Phys. Rev. Lett. 88, 060403 (2002)]. However, it has the advantage that all local observers can know from their own measurements whether their qubits belongs or not to the selected pair.
Vibron-polaron in alpha-helices. II. Two-vibron bound states
Falvo, C; Falvo, Cyril; Pouthier, Vincent
2005-01-01
The two-vibron dynamics associated to amide-I vibrations in a 3D $\\alpha$-helix is described according to a generalized Davydov model. The helix is modeled by three spines of hydrogen-bonded peptide units linked via covalent bonds. It is shown that the two-vibron energy spectrum supports both a two-vibron free states continuum and two kinds of bound states, called TVBS-I and TVBS-II, connected to the trapping of two vibrons onto the same amide-I mode and onto two nearest neighbor amide-I modes belonging to the same spine, respectively. At low temperature, non vanishing interspine hopping constants yield a three dimensional nature of both TVBS-I and TVBS-II which the wave functions extend over the three spines of the helix. At biological temperature, the pairs are confined in a given spine and exhibit the same features as the bound states described within a one-dimensional model. The interplay between the temperature and the 3D nature of the helix is also responsible for the occurrence of a third bound state c...
Gauge invariant formulation of 3 γ decay of particle-antiparticle bound states
Blankleider, B.; Kvinikhidze, A. N.; Silagadze, Z. K.
2015-08-01
We construct the gauge invariant three-photon decay amplitude of particle-antiparticle bound states modeled by the Dyson-Schwinger and Bethe-Salpeter equations. Application to the quark-antiquark (q q ¯ ) bound states is emphasized. An essential aspect of our formulation is that it applies to any underlying quantum field theoretic model of the q q ¯ system, and not just to models, like exact QCD, where the quark self-energy Σ couples to the electromagnetic field solely via dressed quark propagators. In this way, applications to effective field theories and other QCD motivated models are envisioned. The three-photon decay amplitude is constructed by attaching currents to all possible places in the Feynman diagrams contributing to the dressed quark propagator. The gauge invariance of our construction is thus a direct consequence of respecting the underlying structure of the quantum field theory determining the dynamics. In the resultant expression for the three-photon decay amplitude, all the basic ingredients consisting of the bound-state wave function, the final-state interaction q q ¯ t matrix, the dressed quark propagator, and dressed quark currents, are determined by a universal Bethe-Salpeter kernel.
Gauge invariant formulation of 3$\\gamma$ decay of particle-antiparticle bound states
Blankleider, B; Silagadze, Z K
2014-01-01
We construct the gauge invariant three-photon decay amplitude of particle-antiparticle bound states modeled by the Dyson-Schwinger and Bethe-Salpeter equations. Application to the quark-antiquark ($q\\bar{q}$) bound states is emphasized. An essential aspect of our approach is that photons are allowed to couple to the $q\\bar{q}$ system in any way allowed by the given model, i.e., not just via the dressed quark propagator as in exact QCD. In this way, applications to effective field theories and other QCD motivated models are envisioned. The three-photon decay amplitude is constructed by attaching currents to all possible places in the Feynman diagrams contributing to the dressed quark propagator. The gauge invariance of our construction is thus a direct consequence of respecting the underlying structure of the quantum field theory determining the dynamics. In the resultant expression for the three-photon decay amplitude, all the basic ingredients consisting of the bound state wave function, the final-state inte...
Choudhari, Tarun; Deo, Nivedita
2017-01-01
A superconductor-topological insulator-superconductor (S/TI/S) junction having normal region at angle θ is studied theoretically to investigate the junction angle dependency of the Andreev reflection and the formation of the Andreev bound states in the step and planar S/TI/S structures. It is found that the Andreev reflection becomes θ dependent only in the presence of the potential barrier at the TI/S interface. In particular, the step and planar TI/S junction have totally different conductive behavior with bias voltage and potential barrier in the regime of retro and specular Andreev reflection. Interestingly, we find that the elliptical cross section of Dirac cone, an important feature of topological insulator with step surface defect, affects the Fabry-Perot resonance of the Andreev reflection induced Andreev bound states (which become Majorana zero energy states at low chemical potential) in the step S/TI/S structure. Unlike the usual planar S/TI/S structures, we find these ellipticity affected Andreev bound states lead to non-monotonic Josephson super-current in the step S/TI/S structure whose non-monotonicity can be controlled with the use of the potential barrier, which may find applications in nanoelectronics.
Transport through a quantum dot coupled to two Majorana bound states
Zeng, Qi-Bo; Chen, Shu; You, L.; Lü, Rong
2017-08-01
We investigate electron transport inside a ring system composed of a quantum dot (QD) coupled to two Majorana bound states confined at the ends of a one-dimensional topological superconductor nanowire. By tuning the magnetic flux threading through the ring, the model system we consider can be switched into states with or without zero-energy modes when the nanowire is in its topological phase. We find that the Fano profile in the conductance spectrum due to the interference between bound and continuum states exhibits markedly different features for these two different situations, which consequently can be used to detect the Majorana zero-energy mode. Most interestingly, as a periodic function of magnetic flux, the conductance shows 2 π periodicity when the two Majorana bound states are nonoverlapping (as in an infinitely long nanowire) but displays 4 π periodicity when the overlapping becomes nonzero (as in a finite length nanowire). We map the model system into a QD-Kitaev ring in the Majorana fermion representation and affirm these different characteristics by checking the energy spectrum.
Szybisz, Leszek
1996-03-01
Elementary excitations in rather thick symmetric films of liquid 4He at T=0 K are investigated. They are characterized by a momentum ħq parallel to the surface and may be described by bound or continuum states, which are obtained by solving a Bogoliubov-type equation formulated within the framework of the paired-phonon analysis and the hypernetted-chain approximation. Films of coverages nc=0.3 and 0.4 Å-2 confined by simple Gaussian potentials are studied. The excitation spectrum is numerically evaluated by discretizing the associated eigenvalue problem in a finite box. The evolution of the energy levels as a function of the box size is explored. Examples of the calculated energies and wave functions are displayed in a series of figures. Two differing sorts of continuum states may be distinguished. Depending on the behavior of their excitation energies as a function of the box size on the one hand, and the spatial distribution of their wave functions inside the film and in the asymptotic region far apart from the interface layer on the other, the continuum solutions can be separated into two classes of excitations: (a) the ``regular'' continuum states and (b) the ``resonant modes.'' The matrix elements of the particle-hole potential and the penetration factors of the most important states are examined. The lowest-lying branch of states is always bound and for q~qR the structure factor is determined by the contributions originated from the three lowest-lying even states. At q~=qR there is a dramatic transfer of strength from the bound continuation of the hardest ``resonant mode'' to the ripplon excitation. Experimental data of the inelastic structure factor S(q,ħω) may be satisfactorily interpreted on the basis of our calculation. On the other hand, it is shown that for 2.9<=q<=3.9 Å-1 the lowest-lying excitations become surface modes again.
Bound-State Solution of s-Wave Klein-Gordon Equation for Woods-Saxon Potential
Directory of Open Access Journals (Sweden)
Eser Olğar
2015-01-01
Full Text Available The bound-state solution of s-wave Klein-Gordon equation is calculated for Woods-Saxon potential by using the asymptotic iteration method (AIM. The energy eigenvalues and eigenfunctions are obtained for the required condition of bound-state solutions.
Hamer, C. J.
2009-06-01
The energy spectra of the two-magnon bound states in the Heisenberg-Ising antiferromagnet on the square lattice are calculated using series expansion methods. The results confirm an earlier spin-wave prediction of Oguchi and Ishikawa that the bound states vanish into the continuum before the isotropic Heisenberg limit is reached.
The quark-gluon vertex in Landau gauge bound-state studies
Williams, Richard
2015-05-01
We present a practical method for the solution of the quark-gluon vertex for use in Bethe-Salpeter and Dyson-Schwinger calculations. The efficient decomposition into the necessary covariants is detailed, with the numerical algorithm outlined for both real and complex Euclidean momenta. A truncation of the quark-gluon vertex, that neglects explicit back-coupling to enable the application to bound-state calculations, is given together with results for the quark propagator and quark-gluon vertex for different quark flavours. The relative impact of the various components of the quark-gluon vertex is highlighted with the flavour dependence of the effective quark-gluon interaction obtained, thus providing insight for the construction of phenomenological models within the rainbow ladder. Finally, we solve the corresponding Green's functions for complex Euclidean momenta as required in future bound-state calculations.
Radiative bound-state-formation cross-sections for dark matter interacting via a Yukawa potential
Petraki, Kalliopi; de Vries, Jordy
2016-01-01
We calculate the cross-sections for the radiative formation of bound states by dark matter whose interactions are described in the non-relativistic regime by a Yukawa potential. These cross-sections are important for cosmological and phenomenological studies of dark matter with long-range interactions, residing in a hidden sector, as well as for TeV-scale WIMP dark matter. We provide the leading-order contributions to the cross-sections for the dominant capture processes occurring via emission of a vector or a scalar boson. We offer a detailed inspection of their features, including their velocity dependence within and outside the Coulomb regime, and their resonance structure. For pairs of annihilating particles, we compare bound-state formation with annihilation.
Vertical D4-D2-D0 bound states on K3 fibrations and modularity
DEFF Research Database (Denmark)
Bouchard, Vincent; Creutzig, Thomas; Diaconescu, Duiliu-Emanuel;
2016-01-01
An explicit formula is derived for the generating function of vertical D4-D2-D0 bound states on smooth K3 fibered Calabi-Yau threefolds, generalizing previous results of Gholampour and Sheshmani. It is also shown that this formula satisfies strong modularity properties, as predicted by string the...... theory. This leads to a new construction of vector valued modular forms which exhibits some of the features of a generalized Hecke transform.......An explicit formula is derived for the generating function of vertical D4-D2-D0 bound states on smooth K3 fibered Calabi-Yau threefolds, generalizing previous results of Gholampour and Sheshmani. It is also shown that this formula satisfies strong modularity properties, as predicted by string...
Bound States Energies of a Harmonic Oscillator Perturbed by Point Interactions
Ferkous, N.; Boudjedaa, T.
2017-03-01
We determine explicitly the exact transcendental bound states energies equation for a one-dimensional harmonic oscillator perturbed by a single and a double point interactions via Green’s function techniques using both momentum and position space representations. The even and odd solutions of the problem are discussed. The corresponding limiting cases are recovered. For the harmonic oscillator with a point interaction in more than one dimension, divergent series appear. We use to remove this divergence an exponential regulator and we obtain a transcendental equation for the energy bound states. The results obtained here are consistent with other investigations using different methods. Supported by the Algerian Ministry of Higher Education and Scientific Research under the CNEPRU project No. D01720140001
Bound-state field theory approach to proton structure effects in muonic hydrogen
Mohr, Peter J; Sapirstein, J
2013-01-01
A bound-state field theory approach to muonic hydrogen is set up using a variant of the Furry representation in which the lowest-order Hamiltonian describes a muon in the presence of a point Coulomb field, but the origin of the binding field is taken to be three charged quarks in the proton which are modeled as Dirac particles that move freely within a spherical well. Bound-state field theory techniques are used to evaluate one- and two-photon effects. Particular attention is paid to two-photon exchange diagrams, which include the effect of proton polarizability. In addition the modification of the electromagnetic self energy of the proton by the electric field of the muon is examined. Finally, the model is used to carry out a calculation of the static electric polarizability of the proton.
The quark-gluon vertex in Landau gauge bound-state studies
Energy Technology Data Exchange (ETDEWEB)
Williams, Richard [Justus-Liebig University of Giessen, Institute of Theoretical Physics, Giessen (Germany)
2015-05-15
We present a practical method for the solution of the quark-gluon vertex for use in Bethe-Salpeter and Dyson-Schwinger calculations. The efficient decomposition into the necessary covariants is detailed, with the numerical algorithm outlined for both real and complex Euclidean momenta. A truncation of the quark-gluon vertex, that neglects explicit back-coupling to enable the application to bound-state calculations, is given together with results for the quark propagator and quark-gluon vertex for different quark flavours. The relative impact of the various components of the quark-gluon vertex is highlighted with the flavour dependence of the effective quark-gluon interaction obtained, thus providing insight for the construction of phenomenological models within the rainbow ladder. Finally, we solve the corresponding Green's functions for complex Euclidean momenta as required in future bound-state calculations. (orig.)
Baryon-baryon bound states in a (2+1)-dimensional lattice QCD model
Faria da Veiga, Paulo A.; O'Carroll, Michael; Schor, Ricardo
2003-08-01
We consider bound states of two baryons (antibaryons) in lattice QCD in a Euclidean formulation. For simplicity, we analyze an SU(3) theory with a single flavor in 2+1 dimensions and two-dimensional Dirac matrices. For a small hopping parameter 0<κ≪1 and large glueball mass, we recently showed the existence of a (anti)baryonlike particle, with an asymptotic mass of the order of -3 ln κ and with an isolated dispersion curve, i.e., an upper gap property persisting up to near the meson-baryon threshold, which is of order -5 ln κ. Here, we show that there is no baryon-baryon (or antibaryon-antibaryon) bound state solution to the Bethe-Salpeter equation up to the two-baryon threshold, which is approximately -6 ln κ.
Institute of Scientific and Technical Information of China (English)
CHANG Chao-Hsi; CHEN Jiao-Kai; WANG Guo-Li
2006-01-01
We have precisely derived a "rigorous instantaneous formulation" for transitions between two bound states when the bound states are well-described by instantaneous Bethe-Salpeter (BS) equation (i.e. the kernel of the equation is instantaneous"occasionally"). The obtained rigorous instantaneous formulation, in fact, is expressed as an operator sandwiched by two "reduced BS wave functions" properly, while the reduced BS wave functions appearing in the formulation are the rigorous solutions of the instantaneous BS equation, and they may relate to Schr(o)dinger wave functions straightforwardly. We also show that the rigorous instantaneous formulation is gauge-invariant with respect to the Uem(1) transformation precisely, if the concerned transitions are radiative. Some applications of the formulation are outlined.
Optical bound states in the continuum in a single slab with zero refractive index
Li, LiangSheng; Zhang, Jing; Wang, Chong; Zheng, Ning; Yin, Hongcheng
2017-07-01
We have investigated theoretically the reflectivity, quality factor, and eigenfrequency for a single slab with zero refractive index. We demonstrate that optical bound states in the continuum can be achieved by the various zero-refractive-index slabs made of epsilon-near-zero, impedance-machted zero-index, or mu-near-zero materials. Moreover, by analytically investigating the frequency of the resonant reflection and resonant transmission, when the quality factor becomes infinity, these two frequencies are precisely equal. For the mu-near-zero slab, the bound states in the continuum are observed at arbitrary incident angles by analyzing the behaviors of complex eigenfrequencies. Our findings may lead to unprecedented high-quality resonators in metamaterials.
Lower Bounds on the Capacity of the Relay Channel with States at the Source
Directory of Open Access Journals (Sweden)
Abdellatif Zaidi
2009-01-01
Full Text Available We consider a state-dependent three-terminal full-duplex relay channel with the channel states noncausally available at only the source, that is, neither at the relay nor at the destination. This model has application to cooperation over certain wireless channels with asymmetric cognition capabilities and cognitive interference relay channels. We establish lower bounds on the channel capacity for both discrete memoryless (DM and Gaussian cases. For the DM case, the coding scheme for the lower bound uses techniques of rate-splitting at the source, decode-and-forward (DF relaying, and a Gel'fand-Pinsker-like binning scheme. In this coding scheme, the relay decodes only partially the information sent by the source. Due to the rate-splitting, this lower bound is better than the one obtained by assuming that the relay decodes all the information from the source, that is, full-DF. For the Gaussian case, we consider channel models in which each of the relay node and the destination node experiences on its link an additive Gaussian outside interference. We first focus on the case in which the links to the relay and to the destination are corrupted by the same interference; and then we focus on the case of independent interferences. We also discuss a model with correlated interferences. For each of the first two models, we establish a lower bound on the channel capacity. The coding schemes for the lower bounds use techniques of dirty paper coding or carbon copying onto dirty paper, interference reduction at the source and decode-and-forward relaying. The results reveal that, by opposition to carbon copying onto dirty paper and its root Costa's initial dirty paper coding (DPC, it may be beneficial in our setup that the informed source uses a part of its power to partially cancel the effect of the interference so that the uninformed relay benefits from this cancellation, and so the source benefits in turn.
Differential dynamics of RAS isoforms in GDP- and GTP-bound states.
Kapoor, Abhijeet; Travesset, Alex
2015-06-01
RAS subfamily proteins regulates cell growth promoting signaling processes by cycling between active (GTP-bound) and inactive (GDP-bound) states. Different RAS isoforms, though structurally similar, exhibit functional specificity and are associated with different types of cancers and developmental disorders. Understanding the dynamical differences between the isoforms is crucial for the design of inhibitors that can selectively target a particular malfunctioning isoform. In this study, we provide a comprehensive comparison of the dynamics of all the three RAS isoforms (HRAS, KRAS, and NRAS) using extensive molecular dynamics simulations in both the GDP- (total of 3.06 μs) and GTP-bound (total of 2.4 μs) states. We observed significant differences in the dynamics of the isoforms, which rather interestingly, varied depending on the type of the nucleotide bound and the simulation temperature. Both SwitchI (Residues 25-40) and SwitchII (Residues 59-75) differ significantly in their flexibility in the three isoforms. Furthermore, Principal Component Analysis showed that there are differences in the conformational space sampled by the GTP-bound RAS isoforms. We also identified a previously unreported pocket, which opens transiently during MD simulations, and can be targeted to regulate nucleotide exchange reaction or possibly interfere with membrane localization. Further, we present the first simulation study showing GDP destabilization in the wild-type RAS protein. The destabilization of GDP/GTP occurred only in 1/50 simulations, emphasizing the need of guanine nucleotide exchange factors (GEFs) to accelerate such an extremely unfavorable process. This observation along with the other results presented in this article further support our previously hypothesized mechanism of GEF-assisted nucleotide exchange. © 2015 Wiley Periodicals, Inc.
Vertical D4-D2-D0 Bound States on K3 Fibrations and Modularity
Bouchard, Vincent; Creutzig, Thomas; Diaconescu, Duiliu-Emanuel; Doran, Charles; Quigley, Callum; Sheshmani, Artan
2017-03-01
An explicit formula is derived for the generating function of vertical D4-D2-D0 bound states on smooth K3 fibered Calabi-Yau threefolds, generalizing previous results of Gholampour and Sheshmani. It is also shown that this formula satisfies strong modularity properties, as predicted by string theory. This leads to a new construction of vector valued modular forms which exhibit some of the features of a generalized Hecke transform.
Study of -nucleus interaction through the formation of -nucleus bound state
Indian Academy of Sciences (India)
V Jha; B J Roy; A Chatterjee; H Machner
2006-05-01
The question of possible existence of -mesic nuclei is quite intriguing. Answer to this question will deeply enrich our understanding of -nucleus interaction which is not so well-understood. We review the experimental efforts for the search of -mesic nuclei and describe the physics motivation behind it. We present the description of an experiment for the search of -nucleus bound state using the GeV proton beam, currently being performed at COSY.
Vertical D4-D2-D0 bound states on K3 fibrations and modularity
Bouchard, Vincent; Diaconescu, Duiliu-Emanuel; Doran, Charles; Quigley, Callum; Sheshmani, Artan
2016-01-01
An explicit formula is derived for the generating function of vertical D4-D2-D0 bound states on smooth K3 fibered Calabi-Yau threefolds, generalizing previous results of Gholampour and Sheshmani. It is also shown that this formula satisfies strong modularity properties, as predicted by string theory. This leads to a new construction of vector valued modular forms which exhibits some of the features of a generalized Hecke transform.
Phonon dilatation, dressed vibrons and two-vibron bound states localization in an adsorbed nanowire
Pouthier, Vincent,
2006-01-01
A special attention is paid to characterize the two-vibron bound state dynamics of an anharmonic molecular nanostructure coupled with a set of optical phonons. It is shown that the vibron-phonon coupling is responsible for a new dressing mechanism. The vibrons are accompanied by virtual phonons which account for the scaling of each phonon coordinate and for the dilatation of the corresponding wave function. As a result, the dynamics of the dressed vibrons is governed by an effective Hamiltoni...
Vertical D4-D2-D0 bound states on K3 fibrations and modularity
DEFF Research Database (Denmark)
Bouchard, Vincent; Creutzig, Thomas; Diaconescu, Duiliu-Emanuel;
2016-01-01
An explicit formula is derived for the generating function of vertical D4-D2-D0 bound states on smooth K3 fibered Calabi-Yau threefolds, generalizing previous results of Gholampour and Sheshmani. It is also shown that this formula satisfies strong modularity properties, as predicted by string...... theory. This leads to a new construction of vector valued modular forms which exhibits some of the features of a generalized Hecke transform....
Dissecting zero modes and bound states on BPS vortices in Ginzburg-Landau superconductors
Energy Technology Data Exchange (ETDEWEB)
Izquierdo, A. Alonso [Departamento de Matematica Aplicada, Universidad de Salamanca,Facultad de Ciencias Agrarias y Ambientales,Av. Filiberto Villalobos 119, E-37008 Salamanca (Spain); Fuertes, W. Garcia [Departamento de Fisica, Universidad de Oviedo, Facultad de Ciencias,Calle Calvo Sotelo s/n, E-33007 Oviedo (Spain); Guilarte, J. Mateos [Departamento de Fisica Fundamental, Universidad de Salamanca, Facultad de Ciencias,Plaza de la Merced, E-37008 Salamanca (Spain)
2016-05-12
In this paper the zero modes of fluctuation of cylindrically symmetric self-dual vortices are analyzed and described in full detail. These BPS topological defects arise at the critical point between Type II and Type I superconductors, or, equivalently, when the masses of the Higgs particle and the vector boson in the Abelian Higgs model are equal. In addition, novel bound states of Higss and vector bosons trapped by the self-dual vortices at their core are found and investigated.
Dissecting zero modes and bound states on BPS vortices in Ginzburg-Landau superconductors
Alonso-Izquierdo, Alberto; Guilarte, Juan Mateos
2016-01-01
In this paper the zero modes of fluctuation of cylindrically symmetric self-dual vortices are analyzed and described in full detail. These BPS topological defects arise at the critical point between Type II and Type I superconductors, or, equivalently, when the masses of the Higgs particle and the vector boson in the Abelian Higgs model are equal. In addition, novel bound states of Higss and vector bosons trapped by the self-dual vortices at their core are found and investigated.
Benniston, Andrew C; Harriman, Anthony; Li, Peiyi; Patel, Pritesh V; Sams, Craig A
2008-01-01
The rate constant for triplet energy transfer (k(TET)) has been measured in fluid solution for a series of mixed-metal Ru-Os bis(2,2':6',2''-terpyridine) complexes built around a tethered biphenyl-based spacer group. The length of the tether controls the central torsion angle for the spacer, which can be varied systematically from 37 to 130 degrees . At low temperature, but still in fluid solution, the spacer adopts the lowest-energy conformation and k(TET) shows a clear correlation with the torsion angle. A similar relationship holds for the inverse quantum yield for emission from the Ru-terpy donor. Triplet energy transfer is more strongly activated at higher temperature and the kinetic data require analysis in terms of two separate processes. The more weakly activated step involves electron exchange from the first-excited triplet state on the Ru-terpy donor and the size of the activation barrier matches well with that calculated from spectroscopic properties. The pre-exponential factor derived for this process correlates remarkably well with the torsion angle and there is a large disparity in electronic coupling through pi and sigma orbitals on the spacer. The more strongly activated step is attributed to electron exchange from an upper-lying triplet state localized on the Ru-terpy donor. Here, the pre-exponential factor is larger but shows the same dependence on the geometry of the spacer. Strangely, the difference in coupling through pi and sigma orbitals is much less pronounced. Despite internal flexibility around the spacer, k(TET) shows a marked dependence on the torsion angle computed for the lowest-energy conformation.
F(750), We Miss You, as Bound State of 6 Top and 6 Anti top
Nielsen, Holger Frits Bech
2016-01-01
We collect and estimate support for our long speculated "multiple point principle" saying that there should be several vacua all having (compared to the scales of high energy physics) very low energy densities. In pure Standard Model we suggest there being three by "multiple point principle" low energy density vacua, "present", "condensate" and "high field" vacuum. We fit the mass of the in our picture since long speculated bound state of six top and six anti top quarks in three quite {\\em independent ways} and get remarkably within our crude accuracy the {\\em same} mass in all three fits! The new point of the present article is to estimate the bound state mass in what we could call a bag model estimation. The two other fits, which we review, obtain the mass of the bound state by fitting to the multiple point principle prediction of degenerate vacua. Our remarkable agreement of our three mass-fits can be interpreted to mean, that we have calculated at the end the energy densities of the two extra speculated v...
Conformation-Selective Resonant Photoelectron Spectroscopy via Dipole-Bound States of Cold Anions.
Huang, Dao-Ling; Liu, Hong-Tao; Ning, Chuan-Gang; Wang, Lai-Sheng
2015-06-18
Molecular conformation is important in chemistry and biochemistry. Conformers connected by low energy barriers can only be observed at low temperatures and are difficult to be separated. Here we report a new method to obtain conformation-selective spectroscopic information about dipolar molecular radicals via dipole-bound excited states of the corresponding anions cooled in a cryogenic ion trap. We observed two conformers of cold 3-hydroxyphenoxide anions [m-HO(C6H4)O(-)] in high-resolution photoelectron spectroscopy and measured different electron affinities, 18,850(8) and 18,917(5) cm(-1), for the syn and anti 3-hydroxyphenoxy radicals, respectively. We also observed dipole-bound excited states for m-HO(C6H4)O(-) with different binding energies for the two conformers due to the different dipole moments of the corresponding 3-hydroxyphenoxy radicals. Excitations to selected vibrational levels of the dipole-bound states result in conformation-selective photoelectron spectra. This method should be applicable to conformation-selective spectroscopic studies of any anions with dipolar neutral cores.
Bound state, phase separation and superconductivity in presence of Rashba spin-orbit coupling
Kapri, Priyadarshini; Basu, Saurabh
2017-06-01
We have investigated the phase diagram for the t - J model at low electronic densities in presence of Rashba spin-orbit coupling (RSOC). We have rigorously derived a bound state criterion which arises out of a competition between the kinetic energy of the electrons and the exchange coupling between them. Further, we have obtained that the phase diagram consists of three phases, namely, a gas of electrons, a gas of bound pairs, and a fully phase separated state. Subsequently an extension of the pairing scenario is done at finite densities by solving a BCS gap equation. Finite superconducting correlations are observed for J values much lower than that required for the formation of a single bound pair, thereby indicating that pairing in a many particle environment requires weaker interaction strengths than that in the dilute case. We have further obtained that the RSOC increases the transition temperature for a p-wave pairing state, while it diminishes the same for an s-wave pairing correlations.
Meson-baryon bound states in a (2+1)-dimensional strongly coupled lattice QCD model
Neto, Antônio Francisco
2004-08-01
We consider bound states of a meson and a baryon (meson and antibaryon) in lattice QCD in a Euclidean formulation. For simplicity, considering the + parity sector we analyze an SU(3) theory with a single flavor in 2+1 dimensions and two-dimensional Dirac matrices. We work in the strong coupling regime, i.e., in a region of parameters such that the hopping parameter κ is sufficiently small and κ≫g-20, where g-20 is the pure gauge coupling. There is a meson (baryon) particle with asymptotic mass -2 ln κ (-3 ln κ) and an isolated dispersion curve. Here, in a ladder approximation, we show that there is no meson baryon (or meson-antibaryon) bound state solution to the Bethe-Salpeter equation up to the meson-baryon threshold (˜-5 ln κ). The absence of such a bound state is an effect of a spatial range-one repulsive potential that is local in space at order κ3, i.e., the leading order in the hopping parameter κ.
Meson-meson bound states in a (2+1)-dimensional strongly coupled lattice QCD model
Faria da Veiga, Paulo A.; O'Carroll, Michael; Neto, Antônio Francisco
2004-05-01
We consider bound states of two mesons (antimesons) in lattice quantum chromodynamics in an Euclidean formulation. For simplicity, we analyze an SU(3) theory with a single flavor in 2+1 dimensions and two-dimensional Dirac matrices. For a small hopping parameter κ and small plaquette coupling g-20, such that 0
Gluon bound state and asymptotic freedom derived from the Bethe--Salpeter equation
Fukamachi, Hitoshi; Nishino, Shogo; Shinohara, Toru
2016-01-01
In this paper we study the two-body bound states for gluons and ghosts in a massive Yang-Mills theory which is obtained by generalizing the ordinary massless Yang-Mills theory in a manifestly Lorentz covariant gauge. First, we give a systematic derivation of the coupled Bethe-Salpeter equations for gluons and ghosts by using the Cornwall-Jackiw-Tomboulis effective action of the composite operators within the framework of the path integral quantization. Then, we obtain the numerical solutions for the Bethe-Salpeter amplitude representing the simultaneous bound states of gluons and ghosts by solving the homogeneous Bethe-Salpeter equation in the ladder approximation. We study how the inclusion of ghosts affects the two-gluon bound states in the cases of the standing and running gauge coupling constant. Moreover, we show explicitly that the approximate solutions obtained for the gluon-gluon amplitude are consistent with the ultraviolet asymptotic freedom signaled by the negative $\\beta$ function.
Quantization of the Closed Mini-Superspace Models as Bound States
Kung, J H
1995-01-01
Wheeler-DeWitt equation is applied to $k > 0$ Friedmann Robertson Walker metric with various types of matter. It is shown that if the Universe ends in the matter dominated era (e.g., radiation or pressureless gas) with zero cosmological constant, then the resulting Wheeler-DeWitt equation describes a bound state problem. As solutions of a non-degenerate bound state system, the eigen-wave functions are real (Hartle-Hawking) and the usual issue associated with the ambiguity in the boundary conditions for the wave functions is resolved. Furthermore, as a bound state problem, there exists a quantization condition that relates the curvature of the three space with the energy density of the Universe. Incorporating a cosmological constant in the early Universe (inflation) is given as a natural explanation for the large quantum number associated with our Universe, which resulted from the quantization condition. It is also shown that if there is a cosmological constant $\\Lambda > 0$ in our Universe that persists for a...
Fox, Zachary; Neuert, Gregor; Munsky, Brian
2016-08-01
Emerging techniques now allow for precise quantification of distributions of biological molecules in single cells. These rapidly advancing experimental methods have created a need for more rigorous and efficient modeling tools. Here, we derive new bounds on the likelihood that observations of single-cell, single-molecule responses come from a discrete stochastic model, posed in the form of the chemical master equation. These strict upper and lower bounds are based on a finite state projection approach, and they converge monotonically to the exact likelihood value. These bounds allow one to discriminate rigorously between models and with a minimum level of computational effort. In practice, these bounds can be incorporated into stochastic model identification and parameter inference routines, which improve the accuracy and efficiency of endeavors to analyze and predict single-cell behavior. We demonstrate the applicability of our approach using simulated data for three example models as well as for experimental measurements of a time-varying stochastic transcriptional response in yeast.
Upper bound for SL-invariant entanglement measures of mixed states
Osterloh, Andreas
2016-05-01
An algorithm is proposed that serves to handle full-rank density matrices when coming from a lower-rank method to compute the convex roof. This is in order to calculate an upper bound for any polynomial SL-invariant multipartite entanglement measure E . This study exemplifies how this algorithm works based on a method for calculating convex roofs of rank-2 density matrices. It iteratively considers the decompositions of the density matrix into two states each, exploiting the knowledge for the rank-2 case. The algorithm is therefore quasiexact as far as the rank-2 case is concerned, and it also hints where it should include more states in the decomposition of the density matrix. Focusing on the measure of three-way entanglement of qubits (called three-tangle), I show the results the algorithm gives for two states, one of which is the Greenberger-Horne-Zeilinger-Werner (GHZ-W ) state, for which the exact convex roof is known. It overestimates the three-tangle in the state, thereby giving insight into the optimal decomposition the GHZ-W state has. As a proof of principle, I have run the algorithm for the three-tangle on the transverse quantum Ising model. I give qualitative and quantitative arguments why the convex roof should be close to the upper bound found here.
Afzal, Muhammad Imran; Lee, Yong Tak
2016-12-01
Von Neumann and Wigner theorized the bounding and anti-crossing of eigenstates. Experiments have demonstrated that owing to anti-crossing and similar radiation rates, the graphene-like resonance of inhomogeneously strained photonic eigenstates can generate a pseudomagnetic field, bandgaps and Landau levels, whereas exponential or dissimilar rates induce non-Hermicity. Here, we experimentally demonstrate higher-order supersymmetry and quantum phase transitions by resonance between similar one-dimensional lattices. The lattices consisted of inhomogeneous strain-like phases of triangular solitons. The resonance created two-dimensional, inhomogeneously deformed photonic graphene. All parent eigenstates were annihilated. Eigenstates of mildly strained solitons were annihilated at similar rates through one tail and generated Hermitian bounded eigenstates. The strongly strained solitons with positive phase defects were annihilated at exponential rates through one tail, which bounded eigenstates through non-Hermitianally generated exceptional points. Supersymmetry was evident, with preservation of the shapes and relative phase differences of the parent solitons. Localizations of energies generated from annihilations of mildly and strongly strained soliton eigenstates were responsible for geometrical (Berry) and topological phase transitions, respectively. Both contributed to generating a quantum Zeno phase, whereas only strong twists generated topological (Anderson) localization. Anti-bunching-like condensation was also observed.
Why bound-state calculations of tetraquarks should be met with scepticism
Rupp, George
2016-01-01
Recent experimental signals have led to a revival of tetraquarks, the hypothetical $q^2\\bar{q}^2$ hadronic states proposed by Jaffe in 1976 to explain the light scalar mesons. Mesonic structures with exotic quantum numbers have indeed been observed recently, though a controversy persists whether these are true resonances and not merely kinematical threshold enhancements, or otherwise states not of a true $q^2\\bar{q}^2$ nature. Moreover, puzzling non-exotic mesons are also often claimed to have a tetraquark configuration. However, the corresponding model calculations are practically always carried out in pure bound-state approaches, ignoring completely the coupling to asymptotic two-meson states and unitarity, especially the dynamical effects thereof. In this short paper we argue that such static predictions of real tetraquark masses are highly unreliable and provide little evidence of the very existence of such states.
Ndengué, Steve Alexandre; Dawes, Richard; Guo, Hua
2016-06-01
It is commonly understood that the Renner-Teller effect can strongly influence the spectroscopy of molecules through coupling of electronic states. Here we investigate the vibrational bound states and low-lying resonances of the formyl radical treating the Renner-Teller coupled X˜ 2A' and A˜ 2A″ states using the MultiConfiguration Time Dependent Hartree (MCTDH) method. The calculations were performed using the improved relaxation method for the bound states and a recently published extension to compute resonances. A new set of accurate global potential energy surfaces were computed at the explicitly correlated multireference configuration interaction (MRCI-F12) level and yielded remarkably close agreement with experiment in this application and thus enable future studies including photodissociation and collisional dynamics. The results show the necessity of including the large contribution from a Davidson correction in the electronic structure calculations in order to appreciate the relatively small effect of the Renner-Teller coupling on the states considered here.
Bound states in a model of interaction of Dirac field with material plane
Directory of Open Access Journals (Sweden)
Pismak Yu. M.
2016-01-01
Full Text Available In the framework of the Symanzik approach model of the interaction of the Dirac spinor field with the material plane in the 3 + 1-dimensional space is constructed. The model contains eight real parameters characterizing the properties of the material plane. The general solution of the Euler-Lagrange equations of the model and dispersion equations for bound states are analyzed. It is shown that there is a choice of parameters of the model in which the connected states are characterized by dispersion law of a mass-less particle moving along the material plane with the dimensionless Fermi velocity not exceeding one.
Evidence for a Possible Proton-Antiproton Bound State from Lattice QCD
Loan, M
2006-01-01
We have used standard techniques of lattice quantum chromodynamics to look for evidence of the spin-zero six quark flavour singlet state ($J^{PC}=0^{-+}$) observed by BES Collaboration, and to determine the splitting between the mass of the possible proton-antiproton and the mass of two protons, its threshold. Ignoring quark loops and quark annihilation, we find indications that for sufficiently light quarks proton- antiproton is below the $2m_{p}$ threshold, making it a possible six-quark bound state.
Formation Mechanism of Guided Resonances and Bound States in the Continuum in Photonic Crystal Slabs
Gao, Xingwei; Zhen, Bo; Lin, Xiao; Joannopoulos, John D; Soljačić, Marin; Chen, Hongsheng
2016-01-01
We develop a formalism, based on the mode expansion method, to describe the guided resonances and bound states in the continuum (BICs) in photonic crystal slabs with one-dimensional periodicity. This approach provides analytic insights to the formation mechanisms of these states: the guided resonances arise from the transverse Fabry-P\\'erot condition, and the divergence of the resonance lifetimes at the BICs is explained by a destructive interference of radiation from different propagating components inside the slab. We show BICs at the center and on the edge of the Brillouin zone protected by symmetry, as well as BICs at generic wave vectors not protected by symmetry.
NN S-Wave Elastic Cross Section and Possible Bound States in a Constituent Quark Model
Institute of Scientific and Technical Information of China (English)
PANG Hou-Rong; PING Jia-Lun; WANG Fan
2008-01-01
In the framework of a chiral constituent quark model, considering the contributions of π annihilation and one-gluon annihilation, the proton-antiproton s-wave elastic scattering cross section experimental data can be reproduced by adjusting properly one-gluon annihilation coupling constant. After fixing the model parameters, we perform a dynamical calculation for all possible s-wave nucleon-antinucleon states. The results show that there is no s-wave bound state as indicated by a strong enhancement at threshold of pp in J/ψ and B decay.
Variational approach to bound states in scalar-gluon field theory
Energy Technology Data Exchange (ETDEWEB)
Dietz, K.; Romer, H.
1976-10-15
Two variational approaches are employed to attack the bound-state problem of a charged scalar field interacting with an Abelian gauge field. The resulting variational equations allow for a qualitative discussion of all possible physical situations. Boundary conditions play a crucial role in their interpretation. A specially developed perturbation scheme yields hydrogenlike spectra. ''Self-trapping'' solutions and configurations with complete screening of the long-range force are discussed and are shown not to be obtainable by perturbation for small coupling. Metastable states appear for strong coupling. (AIP)
Samala, Nagaprasad Reddy; Mahapatra, S.
2014-06-01
Polycyclic aromatic hydrocarbons (PAHs), in particular, their radical cation (PAH^+), have long been postulated to be the important molecular species in connection with the spectroscopic observations in the interstellar medium. Motivated by numerous important observations by stellar as well as laboratory spectroscopists, we undertook detailed quantum mechanical studies of the structure and dynamics of electronically excited PAH^+ in an attempt to establish possible synergism with the recorded data In this study, we focus on the quantum chemistry and dynamics of the doublet ground (X) and low-lying excited (A, B and C) electronic states of the radical cation of tetracene (Tn), pentacene (Pn), and hexacene (Hn) molecule. This study is aimed to unravel photostability, spectroscopy, and time-dependent dynamics of their excited electronic states. In order to proceed with the theoretical investigations, we construct suitable multistate and multimode Hamiltonian for these systems with the aid of extensive ab initio calculations of their electronic energy surfaces. The diabatic coupling surfaces are derived from the calculated adiabatic electronic energies. First principles nuclear dynamics calculations are then carried out employing the constructed Hamiltonians and with the aid of time-independent and time-dependent quantum mechanical methods. We compared our theoretical results with available photoelectron spectroscopy, zero kinetic energy photoelectron (ZEKE) spectroscopy and matrix isolation spectroscopy (MIS) results. A peak at 8650 Å in the B state spectrum of Tn^+ is in good agreement with the DIB at 8648 Å observed by Salama et al. Similarly in Pn^+, a peak at 8350 Å can be correlated to the DIB at 8321 Å observed by Salama et al. J. Zhang et al., J. Chem. Phys., 128,104301 (2008).; F. Salama, Origins of Life Evol. Biosphere, 28, 349 (1998).; F. Salama et al., Planet. Space Sci., 43, 1165 (1995).; F. Salama et al., Astrophys. J., 526, 265 (1999).; J
Bounded-Error Quantum State Identification and Exponential Separations in Communication Complexity
Gavinsky, D; Kempe, J; Regev, O; Gavinsky, Dmitry; Kempe, Julia; Regev, Oded; Wolf, Ronald de
2005-01-01
We consider the problem of bounded-error quantum state identification: given either state \\alpha_0 or state \\alpha_1, we are required to output `0', `1' or `?' ("don't know"), such that conditioned on outputting `0' or `1', our guess is correct with high probability. The goal is to maximize the probability of not outputting `?'. We prove a direct product theorem: if we're given two such problems, with optimal probabilities a and b, respectively, and the states in the first problem are pure, then the optimal probability for the joint bounded-error state identification problem is O(ab). Our proof is based on semidefinite programming duality and may be of wider interest. Using this result, we present two exponential separations in the simultaneous message passing model of communication complexity. Both are shown in the strongest possible sense. First, we describe a relation that can be computed with O(log n) classical bits of communication in the presence of shared randomness, but needs Omega(n^{1/3}) communicat...
Purwanto, Wirawan; Krakauer, Henry
2009-01-01
We show that the recently developed phaseless auxiliary-field quantum Monte Carlo (AFQMC) method can be used to study excited states, providing an alternative to standard quantum chemistry methods. The phaseless AFQMC approach, whose computational cost scales as M^3-M^4 with system size M, has been shown to be among the most accurate many-body methods in ground state calculations. For excited states, prevention of collapse into the ground state and control of the Fermion sign/phase problem are accomplished by the approximate phaseless constraint with a trial wave function. Using the challenging C2 molecule as a test case, we calculate the potential energy curves of the ground and two low-lying singlet excited states. The trial wave function is obtained by truncating complete active space wave functions, with no further optimization. The phaseless AFQMC results using a small basis set are in good agreement with exact full configuration interaction calculations, while those using large basis sets are in good ag...
Bound states and Cooper pairs of molecules in 2D optical lattices bilayer
Energy Technology Data Exchange (ETDEWEB)
Camacho-Guardian, A.; Dominguez-Castro, G.A.; Paredes, R. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico (Mexico)
2016-08-15
We investigate the formation of Cooper pairs, bound dimers and the dimer-dimer elastic scattering of ultracold dipolar Fermi molecules confined in a 2D optical lattice bilayer configuration. While the energy and their associated bound states are determined in a variational way, the correlated two-molecule pair is addressed as in the original Cooper formulation. We demonstrate that the 2D lattice confinement favors the formation of zero center mass momentum bound states. Regarding the Cooper pairs binding energy, this depends on the molecule populations in each layer. Maximum binding energies occur for non-zero (zero) pair momentum when the Fermi system is polarized (unpolarized). We find an analytic expression for the dimer-dimer effective interaction in the deep BEC regime. The present analysis represents a route for addressing the BCS-BEC crossover in dipolar Fermi gases confined in 2D optical lattices within the current experimental panorama. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Mukund, Sheo; Yarlagadda, Suresh; Bhattacharyya, Soumen; Nakhate, S. G.
2014-01-01
Laser-induced dispersed fluorescence spectra of 58Ni12C molecules, produced in a free-jet apparatus, have been studied. A new low-lying Ω = 0+ state has been observed at Te = 5178 (6) cm-1. Based on previous ab initio calculations this state is plausibly assigned as 0+ spin-orbit component of the first excited 3 Π state. The term energies of vibrational levels up to v = 10 for X1Σ+ ground and v = 3 for Ω = 0+ states have been determined. The harmonic and anharmonic wavenumbers respectively equal to 833 (4) and 6.7 (13) cm-1 for Ω = 0+ state have been measured.
Lie groups and Lie algebras for physicists
Das, Ashok
2015-01-01
The book is intended for graduate students of theoretical physics (with a background in quantum mechanics) as well as researchers interested in applications of Lie group theory and Lie algebras in physics. The emphasis is on the inter-relations of representation theories of Lie groups and the corresponding Lie algebras.
Energy Technology Data Exchange (ETDEWEB)
Sandor, R.K.J.; Blok, H.P.; Harakeh, M.N. (Vrije Univ., Amsterdam (Netherlands). Natuurkundig Lab.); Garg, U. (Vrije Univ., Amsterdam (Netherlands). Natuurkundig Lab. Notre Dame Univ., IN (USA). Dept. of Physics); Jager, C.W. de; Vries, H. de (Nationaal Inst. voor Kernfysica en Hoge-Energiefysica (NIKHEF), Amsterdam (Netherlands). Sectie K); Ponomarev, V.Yu.; Vdovin, A.I. (Joint Inst. for Nuclear Research, Dubna (USSR). Lab. of Theoretical Physics)
1989-12-21
The low-lying quadrupole states in {sup 142}Nd were investigated by inelastic electron scattering. The momentum transfer range covered was 0.5-2.8 fm{sup -1}. The extracted transition charge densities indicate quite different characters for these states. On the basis of a quasiparticle-phonon nuclear model calculation this difference can be understood as arising from an interplay between collective and single-particle aspects. (orig.).
Bound States of the q-Deformed AdS5 x S5 Superstring S-matrix
Hoare, Ben; Miramontes, J Luis
2012-01-01
The investigation of the q deformation of the S-matrix for excitations on the string world sheet in AdS5 x S5 is continued. We argue that due to the lack of Lorentz invariance the situation is more subtle than in a relativistic theory in that the nature of bound states depends on their momentum. At low enough momentum |p|1. This subtlety fixes a problem involving the consistency of crossing symmetry with the relativistic limit found in earlier work. With mirror kinematics, obtained after a double Wick rotation, the bound state structure is simpler and there are no marginally unstable bound states.
Full-potential multiple scattering theory with space-filling cells for bound and continuum states.
Hatada, Keisuke; Hayakawa, Kuniko; Benfatto, Maurizio; Natoli, Calogero R
2010-05-12
We present a rigorous derivation of a real-space full-potential multiple scattering theory (FP-MST) that is free from the drawbacks that up to now have impaired its development (in particular the need to expand cell shape functions in spherical harmonics and rectangular matrices), valid both for continuum and bound states, under conditions for space partitioning that are not excessively restrictive and easily implemented. In this connection we give a new scheme to generate local basis functions for the truncated potential cells that is simple, fast, efficient, valid for any shape of the cell and reduces to the minimum the number of spherical harmonics in the expansion of the scattering wavefunction. The method also avoids the need for saturating 'internal sums' due to the re-expansion of the spherical Hankel functions around another point in space (usually another cell center). Thus this approach provides a straightforward extension of MST in the muffin-tin (MT) approximation, with only one truncation parameter given by the classical relation l(max) = kR(b), where k is the electron wavevector (either in the excited or ground state of the system under consideration) and R(b) is the radius of the bounding sphere of the scattering cell. Moreover, the scattering path operator of the theory can be found in terms of an absolutely convergent procedure in the l(max) --> ∞ limit. Consequently, this feature provides a firm ground for the use of FP-MST as a viable method for electronic structure calculations and makes possible the computation of x-ray spectroscopies, notably photo-electron diffraction, absorption and anomalous scattering among others, with the ease and versatility of the corresponding MT theory. Some numerical applications of the theory are presented, both for continuum and bound states.
Quantum Zeno and anti-Zeno effects in an unstable system with two bound states
Energy Technology Data Exchange (ETDEWEB)
Modi, Kavan [Department of Physics, Center for Complex Quantum Systems, University of Texas at Austin, Austin, TX 78712-1081 (United States)], E-mail: modik@physics.utexas.edu; Shaji, Anil [Department of Physics, Center for Complex Quantum Systems, University of Texas at Austin, Austin, TX 78712-1081 (United States)
2007-08-20
We analyze the experimental observations reported by Fischer et al. [M.C. Fischer, B. Gutierrez-Medina, M.G. Raizen, Phys. Rev. Lett. 87 (2001) 040402] by considering a system of coupled unstable bound quantum states |A> and |B>. The state |B> is coupled to a set of continuum states |C{theta}({omega})>. We investigate the time evolution of |A> when it decays into |C{theta}({omega})> via |B>, and find that frequent measurements on |A> leads to both the quantum Zeno effect and the anti-Zeno effects depending on the frequency of measurements. We show that it is the presence of |B> which allows for the anti-Zeno effect.
Studies on bound-state spectra of Manning-Rosen potential
Roy, Amlan K
2014-01-01
Accurate ro-vibrational energies, eigenfunctions, radial densities, expectation values are presented for the exponential-type Manning-Rosen (MR) potential. Bound states accurate up to ten significant figure are obtained by employing a simple, reliable generalized pseudospectral method. \\emph{All} 55 eigenstates with $n \\leq 10$ are treated for arbitrary values of potential parameters, covering a wide range of interaction, through a \\emph{non-uniform, optimal} spatial radial discretization. A detailed investigation has been made on energy changes with respect to \\emph{screening and other} potential parameters. A systematic estimation of \\emph{critical} screening parameters are given for these eigenstates. Special emphasis has been given to \\emph{higher} states and in the vicinity of \\emph{critical screening} region. A thorough comparison with literature results is made wherever possible. This \\emph{surpasses} the accuracy of \\emph{all} other existing methods currently available. Several \\emph{new} states are r...
Three-body bound states in dipole-dipole interacting Rydberg atoms
Kiffner, Martin; Jaksch, Dieter
2013-01-01
We show that the dipole-dipole interaction between three identical Rydberg atoms can give rise to bound trimer states. The microscopic origin of these states is fundamentally different from Efimov physics. Two stable trimer configurations exist where the atoms form the vertices of an equilateral triangle in a plane perpendicular to a static electric field. The triangle edge length typically exceeds $R\\approx 2\\,\\mu\\text{m}$, and each configuration is two-fold degenerate due to Kramers' degeneracy. The depth of the potential wells and the triangle edge length can be controlled by external parameters. We establish the Borromean nature of the trimer states, analyze the quantum dynamics in the potential wells and describe methods for their production and detection.
Rivera, Nicholas; Hsu, Chia Wei; Zhen, Bo; Buljan, Hrvoje; Joannopoulos, John D.; Soljačić, Marin
2016-09-01
A bound state in the continuum (BIC) is an unusual localized state that is embedded in a continuum of extended states. Here, we present the general condition for BICs to arise from wave equation separability. Then we show that by exploiting perturbations of certain symmetry such BICs can be turned into resonances that radiate with a tailorable directionality and dimensionality. Using this general framework, we construct new examples of separable BICs and resonances that can exist in optical potentials for ultracold atoms, photonic systems, and systems described by tight binding. Such resonances with easily reconfigurable radiation allow for applications such as the storage and release of waves at a controllable rate and direction, as well systems that switch between different dimensions of confinement.
Khan, Md Abdul
2015-01-01
Bound state properties of few single and double-$\\Lambda$ hypernuclei is critically examined in the framework of core-$\\Lambda$ and core+$\\Lambda+\\Lambda$ few-body model applying hyperspherical harmonics expansion method (HHEM). The $\\Lambda\\Lambda$ potential is chosen phenomenologically while the core-$\\Lambda$ potential is obtained by folding a phenomenological $\\Lambda N$ interaction into the density distribution of the core. The depth of the effective $\\Lambda N$ potential is adjusted to reproduce the experimental data for the core-$\\Lambda$ subsystem. The three-body Schr\\"odinger equation is solved by hyperspherical adiabatic approximation (HAA) to get the ground state energy and wave function. The ground state wavefunction is used to construct the supersymmetric partner potential following prescription of supersymmetric quantum mechanics (SSQM) algebra. The newly constructed supersymmetric partner potential is used to solve the three-body Schr\\"odinger equation to get the energy and wavefunction for the...
In-medium ηN interactions and η nuclear bound states
Cieplý, A.; Friedman, E.; Gal, A.; Mareš, J.
2014-05-01
The in-medium ηN interaction near and below threshold is constructed from a free-space chirally-inspired meson-baryon coupled-channel model that captures the physics of the N*(1535) baryon resonance. Nucleon Pauli blocking and hadron self-energies are accounted for. The resulting energy-dependent in-medium interaction is used in self-consistent dynamical calculations of η nuclear bound states. Narrow states of width Γη≲2 MeV are found across the periodic table, beginning with A⩾10, for this in-medium coupled-channel interaction model. The binding energy of the 1sη state increases with A, reaching a value of B1s(η)≈15 MeV. The implications of our self-consistency procedure are discussed with respect to procedures used in other works.
Spinon and bound-state excitation light cones in Heisenberg XXZ chains
de Paula, A. L.; Bragança, H.; Pereira, R. G.; Drumond, R. C.; Aguiar, M. C. O.
2017-01-01
We investigate the out-of-equilibrium dynamics after a local quench that connects two spin-1/2 XXZ chains prepared in the ground state of the Hamiltonian in different phases, one in the ferromagnetic phase and the other in the critical phase. We analyze the time evolution of the on-site magnetization and bipartite entanglement entropy via adaptive time-dependent density matrix renormalization group. In systems with short-range interactions, such as the one we consider, the velocity of information transfer is expected to be bounded, giving rise to a light-cone effect. Interestingly, our results show that, when the anisotropy parameter of the critical chain is sufficiently close to that of the isotropic ferromagnet, the light cone is determined by the velocity of spin-wave bound states that propagate faster than single-particle ("spinon") excitations. Furthermore, we investigate how the system approaches equilibrium in the inhomogeneous ground state of the connected system, in which the ferromagnetic chain induces a nonzero magnetization in the critical chain in the vicinity of the interface.
The effect of bound state dressing in laser assisted radiative recombination
Müller, Robert Alexander; Fritzsche, Stephan; Surzhykov, Andrey
2015-01-01
We present a theoretical study on the recombination of a free electron into the ground state of a hydrogen-like ion in the presence of an external laser field. Emphasis is placed on the effects caused by the laser dressing of the residual ionic bound state. To investigate how this dressing affects the total and angle-differential cross section of laser assisted radiative recombination (LARR) we apply first-order perturbation theory and the separable Coulomb-Volkov-continuum ansatz. Using this approach detailed calculations were performed for low-$Z$ hydrogen like ions and laser intensities in the range from $I_L=10^{11}\\text{W/cm}^2$ to $I_L=10^{13}\\text{W/cm}^2$. It is seen that the total cross section as a function of the laser intensity is remarkably affected by the bound state dressing. Moreover the laser dressing becomes manifest as asymmetries in the angular distribution and the (energy) spectrum of the emitted recombination photons.
Universal three-body bound states in mixed dimensions beyond the Efimov paradigm
Zhang, Pengfei; Yu, Zhenhua
2017-09-01
The Efimov effect was first predicted for three particles interacting at an s -wave resonance in three dimensions. A subsequent study showed that the same effect can be realized by considering two-body and three-body interactions in mixed dimensions. In this work, we consider the three-body problem of two bosonic A atoms interacting with another single B atom in mixed dimensions: The A atoms are confined in a space of dimension dA and the B atom in a space of dimension dB, and there is an interspecies s -wave interaction in a dint-codimensional space accessible to both species. We find that when the s -wave interaction is tuned on resonance, there emerge an infinite series of universal three-body bound states for {dA,dB,dint} ={2 ,2 ,0 } and {2 ,3 ,1 } . Going beyond the Efimov paradigm, the binding energies of these states follow the scaling ln| En|˜-s(n π -θ ) 2/4 , with the scaling factor s being unity for the former case and √{mB(2 mA+mB) }/(mA+mB) for the latter. We discuss the possibility of realizing our mixed-dimensional systems in a cold-atom experiment and how the effects of these universal three-body bound states may be detected.
A search for deeply-bound kaonic nuclear states at J-PARC
Directory of Open Access Journals (Sweden)
Sakaguchi A.
2010-04-01
Full Text Available The J-PARC E15 experiment will be performed to search for the simplest kaonic nuclear bound state, K− pp, by the in-ﬂight 3He(K−,n reaction. The exclusive measurement can be performed by a simultaneous measurement of the missing mass using the primary neutron and the invariant mass via the expected decay, K− pp → Λp → pπ− p. In this report, an overview of the experiment and the preparation status are presented.
Numerical approach to the lowest bound state of muonic three-body systems
Khan, Md Abdul
2015-01-01
In this paper, calculated energies of the lowest bound state of Coulomb three-body systems containing an electron ($e^-$), a negatively charged muon ($\\mu^-$) and a nucleus ($N^{Z+}$) of charge number Z are reported. The 3-body relative wave function in the resulting Schr\\"odinger equation is expanded in the complete set of hyperspherical harmonics (HH). Use of the orthonormality of HH leads to an infinite set of coupled differential equations (CDE) which are solved numerically to get the energy E.
DEFF Research Database (Denmark)
Kutchinsky, Jonatan; Taboryski, Rafael; Sørensen, Claus B.
1999-01-01
We report for the first time enhancement of the supercurrent by means of injection in a mesoscopic three terminal planar SN-SNS device made of Al on GaAs. When a current is injected from one of the superconducting Al electrodes at an injection bias V = Δ(T)/e, the dc Josephson current between the...... the other two superconducting electrodes has a maximum, giving evidence for an enhancement due to a nonequilibrium injection into bound Andreev states of the underlying semiconductor. The effect persists to temperatures where the equilibrium supercurrent has vanished....
Applying the relativistic quantization condition to a three-particle bound state in a periodic box
Hansen, Maxwell T.; Sharpe, Stephen R.
2017-02-01
Using our recently developed relativistic three-particle quantization condition [Phys. Rev. D 90, 116003 (2014), 10.1103/PhysRevD.90.116003; Phys. Rev. D 92, 114509 (2015), 10.1103/PhysRevD.92.114509], we study the finite-volume energy shift of a spin-zero three-particle bound state. We reproduce the result obtained using nonrelativistic quantum mechanics by Meißner et al. in [Phys. Rev. Lett. 114, 091602 (2015), 10.1103/PhysRevLett.114.091602] and generalize the result to a moving frame.
Andreev reflection properties in a parallel mesoscopic circuit with Majorana bound states
Energy Technology Data Exchange (ETDEWEB)
Mu, Jin-Tao; Han, Yu [Physics Department, Liaoning University, Shenyang 110036 (China); Gong, Wei-Jiang, E-mail: gwj@mail.neu.edu.cn [College of Sciences, Northeastern University, Shenyang 110819 (China)
2017-03-15
We investigate the Andreev reflection in a parallel mesoscopic circuit with Majorana bound states (MBSs). It is found that in such a structure, the Andreev current can be manipulated in a highly efficient way, by the adjustment of bias voltage, dot levels, inter-MBS coupling, and the applied magnetic flux. Besides, the dot-MBS coupling manner is an important factor to modulate the Andreev current, because it influences the period of the conductance oscillation. By discussing the underlying quantum interference mechanism, the Andreev-reflection property is explained in detail. We believe that all the results can assist to understand the nontrivial role of the MBSs in driving the Andreev reflection.
Electron-electron bound states in parity-preserving QED{sub 3}
Energy Technology Data Exchange (ETDEWEB)
Belich, H.; Helayel-Neto, J.A. [Universidade Catolica do Petropolis, RJ (Brazil). Grupo de Fisica Teorica]|[Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas; Cima, O.M. del [Universidade Catolica do Petropolis, RJ (Brazil). Grupo de Fisica Teorica; Ferreira Junior, M.M. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas]|[Maranhao Univ., Sao Luis, MA (Brazil). Dept. de Fisica
2002-04-01
By considering the Higgs mechanism in the framework of a parity-preserving Planar Quantum Electrodynamics, one shows that an attractive electron-electron interaction may dominate. The e{sup -}e{sup -} interaction potential emerges as the non-relativistic limit of the Moeller scattering amplitude and it results attractive with a suitable choice of parameters. Numerically values of the e{sup -}e{sup -} binding energy are obtained by solving the two-dimensional Schroedinger equation. The existence of bound states is a strong indicative that this model may be adopted to address the pairing mechanism of high-T{sub c} superconductivity. (author)
Search for the eta-mesic Helium bound state with the WASA-at-COSY facility
Skurzok, M; Rundel, O; Moskal, P
2015-01-01
We performed a search for 4He-eta bound state with high statistics and high acceptance with the WASA-at-COSY facility using a ramped beam technique. The signature of eta-mesic nuclei is searched for in dd -> 3Henpi0 and dd -> 3Heppi- reactions by the measurement of the excitation functions in the vicinity of the {\\eta} production threshold. This paper presents the experimental method and the preliminary results of the data analysis for dd -> 3Henpi0 process.
Formation of bound states of electrons in spherically symmetric oscillations of plasma
Dvornikov, Maxim
2010-01-01
We study spherically symmetric oscillations of electrons in plasma in frames of the classical electrodynamics. First we analyze the electromagnetic potentials for the system of radially oscillating charged particles. Then we consider both free and forced spherically symmetric oscillations of electrons. Finally we discuss the interaction between radially oscillating electrons through the exchange of ion acoustic waves. It is obtained that the effective potential of this interaction can be attractive and can transcend the Debye-Hueckel potential. We suggest that oscillating electrons can form bound states at the initial staged of the spherical plasma structure evolution. The application of the obtained results to the theory of natural plasmoids are considered.
Cygnus X-3: A source of highly symmetric quark bound states. [Cyg X-3
Energy Technology Data Exchange (ETDEWEB)
Horvath, J.E.; Benvenuto, O.G. (Departamento de Fisica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 49 y 115, Casilla de Correo 67, 1900 La Plata (Argentina) Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata (Argentina))
1990-06-01
The point source Cygnus X-3 continues to show puzzling features related to underground modulated muon signals and also an excess of hadron groups recently reported. We propose that the neutral particle responsible for these unusual facts could be a highly symmetric bound QCD state (quark-alpha) recently hypothesized. Interactions of these primaries with ordinary matter and astrophysical expectations are addressed and it is concluded that this proposal is in principle capable of providing some desirable ingredients for an explanation of the data.
The beauty of impurities: Two revivals of Friedel's virtual bound-state concept
Georges, Antoine
2016-03-01
Jacques Friedel pioneered the theoretical study of impurities and magnetic impurities in metals. He discovered Friedel oscillations, introduced the concept of virtual bound-state, and demonstrated that the charge on the impurity is related to the scattering phase-shift at the Fermi level (Friedel sum-rule). After a brief review of some of these concepts, I describe how they proved useful in two new contexts. The first one concerns the Coulomb blockade in quantum dots, and its suppression by the Kondo effect. The second one is the dynamical mean-field theory of strong electronic correlations. xml:lang="fr"
Analytical perspective for bound states in the continuum in photonic crystal slabs.
Yang, Yi; Peng, Chao; Liang, Yong; Li, Zhengbin; Noda, Susumu
2014-07-18
We investigate the formation of photonic bound states in the continuum (BICs) in photonic crystal slabs from an analytical perspective. Unlike the stationary at-Γ BICs which originate from the geometric symmetry, the tunable off-Γ BICs are due to the weighted destructive via the continuum interference in the vicinity of accidental symmetry when the majority of the radiation is precanceled. The symmetric compatible nature of the off-Γ BICs leads to a trapping of light that can be tuned through continuously varying the wave vector. With the analytical approach, we explain a reported experiment and predict the existence of a new BIC at an unrevealed symmetry.
Effect of the Velocity-Dependent Potentials on the Bound State Energy Eigenvalues
Institute of Scientific and Technical Information of China (English)
O.Bayrak; A.Soylu; I.Boztosun
2011-01-01
We investigate the effect of isotropic velocity-dependent potentials on the bound state energy eigenvalues for the first time for any quantum states of the Coulomb and harmonic oscillator potentials within the framework of the asymptotic iteration method. When the velocity-dependent term is selected as a constant parameter po, we present that the energy eigenvalues can be obtained analytically for both Coulomb and harmonic oscillator potentials. However, when the velocity-dependent term is considered as a harmonic oscillator type poΥ2, taking the velocity-dependent term as a perturbation, we present how to obtain the energy eigenvalues of the Coulomb and harmonic oscillator potentials for any n and (e) quantum states by using perturbation expansion and numerical calculations in the asymptotic iteration method procedure.%@@ We investigate the effect of isotropic velocity-dependent potentials on the bound state energy eigenvalues for the first time for any quantum states of the Coulomb and harmonic oscillator potentials within the framework of the asymptotic iteration method.When the velocity-dependent term is selected as a constant parameter po,we present that the energy eigenvalues can be obtained analytically for both Coulomb and harmonic oscillator potentials.However, when the velocity-dependent term is considered as a harmonic oscillator type por2, taking the velocity-dependent term as a perturbation, we present how to obtain the energy eigenvalues of the Coulomb and harmonic oscillator potentials for any n and e quantum states by using perturbation expansion and numerical calculations in the asymptotic iteration method procedure.
Class of PPT bound entangled states associated to almost any set of pure entangled states
Piani, M
2006-01-01
We analyze a class of entangled states for bipartite $d \\otimes d$ systems, with $d$ non-prime. The entanglement of such states is revealed by the construction of canonically associated entanglement witnesses. The structure of the states is very simple and similar to the one of isotropic states: they are a mixture of a separable and a pure entangled state whose supports are orthogonal. Despite such simple structure, in an opportune interval of the mixing parameter their entanglement is not revealed by partial transposition nor by the realignment criterion, i.e. by any permutational criterion in the bipartite setting. In the range in which the states are Positive under Partial Transposition (PPT), they are not distillable; on the other hand, the states in the considered class are provably distillable as soon as they are Nonpositive under Partial Transposition (NPT). The states are associated to any set of more than two pure states. The analysis is extended to the multipartite setting. By an opportune selection...
K− absorption on two nucleons and ppK− bound state search in the Σ0p final state
Directory of Open Access Journals (Sweden)
O. Vázquez Doce
2016-07-01
Full Text Available We report the measurement of K− absorption processes in the Σ0p final state and the first exclusive measurement of the two nucleon absorption (2NA with the KLOE detector. The 2NA process without further interactions is found to be 9% of the sum of all other contributing processes, including absorption on three and more nucleons or 2NA followed by final state interactions with the residual nucleons. We also determine the possible contribution of the ppK− bound state to the Σ0p final state. The yield of ppK−/Kstop− is found to be (0.044±0.009stat−0.005+0.004syst⋅10−2 but its statistical significance based on an F-test is only 1σ.
Relativistic two-body bound states in scalar QFT: variational basis-state approach
Energy Technology Data Exchange (ETDEWEB)
Emami-Razavi, Mohsen [Centre for Research in Earth and Space Science, York University, Toronto, Ontario, M3J 1P3 (Canada); Darewych, Jurij W [Department of Physics and Astronomy, York University, Toronto, Ontario, M3J 1P3 (Canada)
2006-08-15
We use the Hamiltonian formalism of quantum field theory and the variational basis-state method to derive relativistic coupled-state wave equations for scalar particles interacting via a massive or massless mediating scalar field (the scalar Yukawa model). A variational trial state comprised of two and four Fock-space states is used to derive coupled wave equations for a relativistic two (and four) body system. Approximate, variational two-body ground-state solutions of the relativistic equations are obtained for various strengths of coupling, for both massive and massless mediating fields. The results show that the inclusion of virtual pairs has a large effect on the two-body binding energy at strong coupling. A comparison of the two-body binding energies with other calculations is presented.
Goldfield, Evelyn M.; Kirby, Kate P.
1987-01-01
Configuration interaction wave functions, potential energy curves, and dipole moment functions have been calculated for the four lowest 3Sigma(-) and the three lowest 3Pi states and 5Sigma(-) states of NH. The electronic wave functions were constructed to give a balanced description of valence-Rydberg interactions. Two repulsive states have been identified as important photodissociation pathways. Spectroscopic constants are presented for the bound states, and results are compared to other theoretical and experimental work. The possible predissociation of the A 3Pi state by the 1 5Sigma(-) state is discussed.
Goldfield, Evelyn M.; Kirby, Kate P.
1987-01-01
Configuration interaction wave functions, potential energy curves, and dipole moment functions have been calculated for the four lowest 3Sigma(-) and the three lowest 3Pi states and 5Sigma(-) states of NH. The electronic wave functions were constructed to give a balanced description of valence-Rydberg interactions. Two repulsive states have been identified as important photodissociation pathways. Spectroscopic constants are presented for the bound states, and results are compared to other theoretical and experimental work. The possible predissociation of the A 3Pi state by the 1 5Sigma(-) state is discussed.
Widmer, L A; Stelling, J; Doyle, F J
2013-10-28
Using the (slow-scale) linear noise approximation, we give parameter-independent bounds to the substrate and product intrinsic noise variance for the stochastic Michaelis-Menten approximation at steady state.
Hsieh, Timothy H; Fu, Liang
2012-03-09
The recently discovered superconductor Cu(x)Bi2Se3 is a candidate for three-dimensional time-reversal-invariant topological superconductors, which are predicted to have robust surface Andreev bound states hosting massless Majorana fermions. In this work, we analytically and numerically find the linearly dispersing Majorana fermions at k=0, which smoothly evolve into a new branch of gapless surface Andreev bound states near the Fermi momentum. The latter is a new type of Andreev bound states resulting from both the nontrivial band structure and the odd-parity pairing symmetry. The tunneling spectra of these surface Andreev bound states agree well with a recent point-contact spectroscopy experiment [S. Sasaki et al., Phys. Rev. Lett. 107, 217001 (2011)] and yield additional predictions for low temperature tunneling and photoemission experiments.
Weak Lie symmetry and extended Lie algebra
Energy Technology Data Exchange (ETDEWEB)
Goenner, Hubert [Institute for Theoretical Physics, Friedrich-Hund-Platz 1, University of Goettingen, D-37077 Gottingen (Germany)
2013-04-15
The concept of weak Lie motion (weak Lie symmetry) is introduced. Applications given exhibit a reduction of the usual symmetry, e.g., in the case of the rotation group. In this context, a particular generalization of Lie algebras is found ('extended Lie algebras') which turns out to be an involutive distribution or a simple example for a tangent Lie algebroid. Riemannian and Lorentz metrics can be introduced on such an algebroid through an extended Cartan-Killing form. Transformation groups from non-relativistic mechanics and quantum mechanics lead to such tangent Lie algebroids and to Lorentz geometries constructed on them (1-dimensional gravitational fields).
Low energy behavior of astrophysical S factor in radiative captures to loosely bound final states
Mukhamedzhanov, A M
2002-01-01
The low-energy behavior of the astrophysical S-factor for E1 direct radiative captures a(p,gamma)b leading to loosely bound final states (b=a+p) is investigated. We derive a first-order integral representation for S(E) and focus on the properties around zero energy. We show that it is the competition between various effects, namely the remnant Coulomb barrier, the initial and final centrifugal barriers and the binding energy, that defines the behavior of the S(E->0). Contrary to previous findings, we prove that S(E->0) is not determined by the pole corresponding to the bound state. The derivative S'(0) increases with the increase of the centrifugal barrier, while it decreases with the charge of the target. For l_i=l_f+1 the increase of the binding energy of the final nucleus increases the derivative S'(0) while for l_i=l_f-1 the opposite effect is found. We make use of our findings to explain the low energy behavior of the S-factors related to some notorious capture reactions: 7Be(p, gamma)8B, 14N(p,gamma)15O...