Design of a positioning system for a holographic otoscope
Dobrev, I.; Flores Moreno, J. M.; Furlong, C.; Harrington, E. J.; Rosowski, J. J.; Scarpino, C.
2010-08-01
Current ear examination procedures provide mostly qualitative information which results in insufficient or erroneous description of the patient's hearing. Much more quantitative and accurate results can be achieved with a holographic otoscope system currently under development. Various ways of accurate positioning and stabilization of the system in real-life conditions are being investigated by this project in an attempt to bring this new technology to the hospitals and clinics, in order to improve the quality of the treatments and operations of the human ear. The project is focused at developing a mechatronic system capable of positioning the holographic otoscope to the patient's ear and maintaining its relative orientation during the examination. The system will be able to be guided by the examiner, but it will maintain the chosen position automatically. To achieve that, various trajectories are being measured for existing otoscopes being guided by doctors in real medical conditions. Based on that, various kinematic configurations are to be synthesized and their stability and accuracy will be simulated and optimized with FEA. For simplification, the mechanism will contain no actuators, but only adjustable friction elements in a haptic feedback control system. This renders the positioning system safe and easily applicable to current examination rooms. Other means of stabilization of the system are being investigated such as custom designed packaging of all of the otoscope subsystems, interferometrically compensating for the heartbeat induced vibration of the tympanic membrane as well as methods for monitoring and active response to the motion of the patient's head.
Development of an optoelectronic holographic platform for otolaryngology applications
Harrington, Ellery; Dobrev, Ivo; Bapat, Nikhil; Flores, Jorge Mauricio; Furlong, Cosme; Rosowski, John; Cheng, Jeffery Tao; Scarpino, Chris; Ravicz, Michael
2010-08-01
In this paper, we present advances on our development of an optoelectronic holographic computing platform with the ability to quantitatively measure full-field-of-view nanometer-scale movements of the tympanic membrane (TM). These measurements can facilitate otologists' ability to study and diagnose hearing disorders in humans. The holographic platform consists of a laser delivery system and an otoscope. The control software, called LaserView, is written in Visual C++ and handles communication and synchronization between hardware components. It provides a user-friendly interface to allow viewing of holographic images with several tools to automate holography-related tasks and facilitate hardware communication. The software uses a series of concurrent threads to acquire images, control the hardware, and display quantitative holographic data at video rates and in two modes of operation: optoelectronic holography and lensless digital holography. The holographic platform has been used to perform experiments on several live and post-mortem specimens, and is to be deployed in a medical research environment with future developments leading to its eventual clinical use.
Otoscopic diagnosis of otitis media.
Isaacson, Glenn
2016-12-01
Accurate diagnosis of otitis media is important to prevent suffering and complications when infection is present, and unnecessary antibiotic use when infection is absent. The usual signs and symptoms of acute otitis media are unreliable guides in infants and young children. Similarly, middle ear effusions may present with little discomfort in older children. We therefore depend on examination of the tympanic membrane with an otoscope to make most diagnoses. This article aims to improve the accuracy of middle ear diagnosis by pneumatic otoscopy. It includes descriptions and photographs of the normal ear drum and illustrates the pathologic changes seen in acute otitis media, long-standing eustachian tube dysfunction and otitis media with effusion.
Development of terahertz otoscope for diagnosing otitis media (Conference Presentation)
Jeon, Tae-In; Ji, Young Bin; Bark, Hyeon Sang; Noh, Sam Kyu; Oh, Seung Jae
2017-03-01
A novel terahertz (THz) otoscope is designed and fabricated to help physicians to diagnose otitis media (OM) with both THz diagnostics and conventional optical diagnostics. The inclusion of indium tin oxide (ITO) glass in the THz otoscope allows physicians to diagnose OM with both THz and conventional optical diagnostics. To determine THz diagnostics for OM, we observed reflection signals from samples behind a thin dielectric film and found that the presence of water behind the membrane could be distinguished based on THz pulse shape. We verified the potential of this tool for diagnosing OM using mouse skin tissue and a human tympanic membrane samples prior to clinical application. The presence of water absorbed by the human membrane was easily distinguished based on differences in pulse shapes and peak-to-peak amplitudes of reflected THz pulses. The potential for early OM diagnosis using the THz otoscope was confirmed by alteration of THz pulse depending on water absorption level.
Hu, Wenping; Gong, Xiong; Zhan, Xiaowei; Fu, Hongbing; Bjornholm, Thomas
2012-01-01
Written by internationally recognized experts in the field with academic as well as industrial experience, this book concisely yet systematically covers all aspects of the topic.The monograph focuses on the optoelectronic behavior of organic solids and their application in new optoelectronic devices. It covers organic electroluminescent materials and devices, organic photonics, materials and devices, as well as organic solids in photo absorption and energy conversion. Much emphasis is laid on the preparation of functional materials and the fabrication of devices, from materials synthesis a
A short-wave infrared otoscope for middle ear disease diagnostics (Conference Presentation)
Carr, Jessica A.; Valdez, Tulio; Bruns, Oliver; Bawendi, Moungi
2016-02-01
Otitis media, a range of inflammatory conditions of the middle ear, is the second most common illness diagnosed in children. However, the diagnosis can be challenging, particularly in pediatric patients. Otitis media is commonly over-diagnosed and over-treated and has been identified as one of the primary factors in increased antibiotic resistance. We describe the development of a short-wave infrared (SWIR) otoscope for objective middle ear effusion diagnosis. The SWIR otoscope can unambiguously detect the presence of middle ear fluid based on its strong light absorption in the SWIR. This absorption causes a stark, visual contrast between the presence and absence of fluid behind the tympanic membrane. Additionally, when there is no middle ear fluid, the deeper tissue penetration of SWIR light allows the SWIR otoscope to better visualize middle ear anatomy through the tympanic membrane than is possible with visible light. We demonstrate that in healthy, adult human ears, SWIR otoscopy can image a range of middle ear anatomy, including landmarks of the entire ossicular chain, the promontory, the round window niche, and the chorda tympani. We suggest that SWIR otoscopy can provide valuable diagnostic information complementary to that provided by visible pneumotoscopy in the diagnosis of middle ear effusions, otitis media, and other maladies of the middle ear.
Directory of Open Access Journals (Sweden)
Wang Zhihuan
2015-12-01
Full Text Available Semiconductor nanowires have been used in a variety of passive and active optoelectronic devices including waveguides, photodetectors, solar cells, light-emitting diodes (LEDs, lasers, sensors, and optical antennas. We review the optical properties of these nanowires in terms of absorption, guiding, and radiation of light, which may be termed light management. Analysis of the interaction of light with long cylindrical/hexagonal structures with subwavelength diameters identifies radial resonant modes, such as Leaky Mode Resonances, or Whispering Gallery modes. The two-dimensional treatment should incorporate axial variations in “volumetric modes,”which have so far been presented in terms of Fabry–Perot (FP, and helical resonance modes. We report on finite-difference timedomain (FDTD simulations with the aim of identifying the dependence of these modes on geometry (length, width, tapering, shape (cylindrical, hexagonal, core–shell versus core-only, and dielectric cores with semiconductor shells. This demonstrates how nanowires (NWs form excellent optical cavities without the need for top and bottommirrors. However, optically equivalent structures such as hexagonal and cylindrical wires can have very different optoelectronic properties meaning that light management alone does not sufficiently describe the observed enhancement in upward (absorption and downward transitions (emission of light inNWs; rather, the electronic transition rates should be considered. We discuss this “rate management” scheme showing its strong dimensional dependence, making a case for photonic integrated circuits (PICs that can take advantage of the confluence of the desirable optical and electronic properties of these nanostructures.
DEFF Research Database (Denmark)
Ramanujam, P.S.; Holme, NCR; Berg, RH
1999-01-01
A Two-dimensional holographic memory for archival storage is described. Assuming a coherent transfer function, an A4 page can be stored at high resolution in an area of 1 mm(2). Recently developed side-chain liquid crystalline azobenzene polyesters are found to be suitable media for holographic...... storage. They exhibit high resolution, high diffraction efficiency, have long storage life, are fully erasable and are mechanically stable....
Sutcliffe, Paul M.
Skyrmions are topological solitons that describe baryons within a nonlinear theory of pions. In holographic QCD, baryons correspond to topological solitons in a bulk theory with an extra spatial dimension: thus the three-dimensional Skyrmion lifts to a four-dimensional holographic Skyrmion in the bulk. We begin this review with a description of the simplest example of this correspondence, where the holographic Skyrmion is exactly the self-dual Yang-Mills instanton in flat space. This places an old result of Atiyah and Manton within a holographic framework and reveals that the associated Skyrme model extends the nonlinear pion theory to include an infinite tower of vector mesons, with specific couplings for a BPS theory. We then describe the more complicated curved space version that arises from the string theory construction of Sakai and Sugimoto. The basic concepts remain the same but the technical difficulty increases as the holographic Skyrmion is a curved space version of the Yang-Mills instanton, so self-duality and integrability are lost. Finally, we turn to a low-dimensional analogue of holographic Skyrmions, where aspects such as multi-baryons and finite baryon density are amenable to both numerical computation and an approximate analytic treatment.
Holographic Optical Data Storage
Timucin, Dogan A.; Downie, John D.; Norvig, Peter (Technical Monitor)
2000-01-01
, and security medium as well. The evolution of holographic optical memories has followed a path not altogether different from holography itself, with several cycles of alternating interest over the past four decades. P. J. van Heerden is widely credited for being the first to elucidate the principles behind holographic data storage in a 1963 paper, predicting bit storage densities on the order of 1/lambda(sup 3) with source wavelength lambda - a fantastic capacity of nearly 1 TB/cu cm for visible light! The science and engineering of such a storage paradigm was heavily pursued thereafter, resulting in many novel hologram multiplexing techniques for dense data storage, as well as important advances in holographic recording materials. Ultimately, however, the lack of such enabling technologies as compact laser sources and high performance optical data I/O devices dampened the hopes for the development of a commercial product. After a period of relative dormancy, successful applications of holography in other arenas sparked a renewed interest in holographic data storage in the late 1980s and the early 1990s. Currently, with most of the critical optoelectronic device technologies in place and the quest for an ideal holographic recording medium intensified, holography is once again considered as one of several future data storage paradigms that may answer our constantly growing need for higher-capacity and faster-access memories.
Aref'eva, Irina
2016-01-01
There are successful applications of the holographic AdS/CFT correspondence to high energy and condensed matter physics. We apply the holographic approach to photosynthesis that is an important example of nontrivial quantum phenomena relevant for life which is being studied in the emerging field of quantum biology. Light harvesting complexes of photosynthetic organisms are many-body quantum systems, in which quantum coherence has recently been experimentally shown to survive for relatively long time scales even at the physiological temperature despite the decohering effects of their environments. We use the holographic approach to evaluate the time dependence of entanglement entropy and quantum mutual information in the Fenna-Matthews-Olson (FMO) protein-pigment complex in green sulfur bacteria during the transfer of an excitation from a chlorosome antenna to a reaction center. It is demonstrated that the time evolution of the mutual information simulating the Lindblad master equation in some cases can be obt...
Halyo, E
2004-01-01
Using the de Sitter/CFT correspondence we describe a scenario of holographic inflation which is driven by a three dimensional boundary field theory. We find that inflationary constraints severely restrict the $\\beta$--function, the anomalous dimensions and the value of the $C$--function of the boundary theory. The scenario has model independent predictions such as $\\epsilon<< \\eta$, $n_T<0.04$, $P_{tensor}/P_{scalar}<0.08$ and $H<10^{14} GeV$. We consider some simple boundary theories and find that they do not lead to inflation. Thus, building an acceptable holographic inflation model remains a challenge. We also describe holographic quintessence and find that it closely resembles a cosmological constant.
Odhner, Jefferson E.
2016-07-01
Holographic optical elements (HOEs) work on the principal of diffraction and can in some cases replace conventional optical elements that work on the principal of refraction. An HOE can be thinner, lighter, can have more functionality, and can be lower cost than conventional optics. An HOE can serve as a beam splitter, spectral filter, mirror, and lens all at the same time. For a single wavelength system, an HOE can be an ideal solution but they have not been widely accepted for multispectral systems because they suffer from severe chromatic aberration. A refractive optical system also suffers from chromatic aberration but it is generally not as severe. To color correct a conventional refractive optical system, a flint glass and a crown glass are placed together such that the color dispersion of the flint and the crown cancel each other out making an achromatic lens (achromat) and the wavelengths all focus to the same point. The color dispersion of refractive lenses and holographic lenses are opposite from each other. In a diffractive optical system, long wavelengths focus closer (remember for HOEs: RBM "red bends more") than nominal focus while shorter wavelengths focus further out. In a refractive optical system, it is just the opposite. For this reason, diffractives can be incorporated into a refractive system to do the color correction and often cut down on the number of optical elements used [1.]. Color correction can also be achieved with an all-diffractive system by combining a holographic optical element with its conjugate. In this way the color dispersion of the first holographic optical element can be cancelled by the color dispersion of the second holographic optic. It is this technique that will be exploited in this paper to design a telescope made entirely of holographic optical elements. This telescope could be more portable (for field operations) the same technique could be used to make optics light enough for incorporation into a UAV.
Anninos, Dionysios; Denef, Frederik; Peeters, Lucas
2013-01-01
We establish the existence of stable and metastable stationary black hole bound states at finite temperature and chemical potentials in global and planar four-dimensional asymptotically anti-de Sitter space. We determine a number of features of their holographic duals and argue they represent structural glasses. We map out their thermodynamic landscape in the probe approximation, and show their relaxation dynamics exhibits logarithmic aging, with aging rates determined by the distribution of barriers.
Newton, Heide M; Rosenkrantz, Wayne S; Muse, Russell; Griffin, Craig E
2006-04-01
The objective of this study was to evaluate the relative efficacy of otoscope cone cleaning and disinfection methods commonly used in veterinary practices. Using sterile technique, 60 new gas-sterilized 4-mm otoscope cones were inoculated with a broth culture of 1.5 billion Pseudomonas aeruginosa bacteria per mL then allowed to dry for 10 min. Six study groups of 10 cones each were created. Group 1 served as positive control and received no cleaning or disinfection. Group 2 cones were wiped with sterile cotton-tipped applicators and gauze then rinsed with water. Group 3 cones were wiped with 70% isopropyl alcohol. Group 4 cones were scrubbed in a speculum cleaner with Cetylcide II solution (Cetylite Industries, Inc., Pennsauken, NJ). Groups 5 and 6 cones were soaked for 20 min in Cetylcide II and chlorhexidine gluconate 2% solutions, respectively. Using sterile technique and after 10-15 min drying time, the cones were swabbed in a consistent pattern, and samples were submitted for quantitative culture. Culture results showed no growth from cones soaked in Cetylcide II or chlorhexidine solutions. Two of the 10 cones wiped with alcohol, 3/10 cones wiped then rinsed with water, and 3/10 cones scrubbed with the speculum cleaner showed growth of P. aeruginosa. All (10/10) cones in the control group showed heavy growth of P. aeruginosa. These results show that P. aeruginosa can survive on otoscope cones cleaned and disinfected by several commonly used methods. Further study is needed to determine practical and optimal cleaning and disinfection methods for otoscope cones.
Palais, Joseph C.; Miller, Mark E.
1996-09-01
A unique method for the construction and display of a 3D holographic movie is developed. An animated film is produced by rotating a 3D object in steps between successive holographic exposures. Strip holograms were made on 70-mm AGFA 8E75 Holotest roll film. Each hologram was about 11-mm high and 55-mm high and 55-mm wide. The object was rotated 2 deg between successive exposures. A complete cycle of the object motion was recorded on 180 holograms using the lensless Fourier transform construction. The ends of the developed film were spliced together to produce a continuous loop. Although the film moves continuously on playback and there is not shutter, there is no flicker or image displacement because of the Fourier transform hologram construction, as predicted by the theoretical analysis. The movie can be viewed for an unlimited time because the object motion is cyclical and the film is continuous. The film is wide enough such that comfortable viewing with both eyes is possible, enhancing the 3D effect. Viewers can stand comfortably away from the film since no viewing slit or aperture is necessary. Several people can simultaneously view the movie.
Integrated silicon optoelectronics
Zimmermann, Horst
2000-01-01
'Integrated Silicon Optoelectronics'assembles optoelectronics and microelectronics The book concentrates on silicon as the major basis of modern semiconductor devices and circuits Starting from the basics of optical emission and absorption and from the device physics of photodetectors, the aspects of the integration of photodetectors in modern bipolar, CMOS, and BiCMOS technologies are discussed Detailed descriptions of fabrication technologies and applications of optoelectronic integrated circuits are included The book, furthermore, contains a review of the state of research on eagerly expected silicon light emitters In order to cover the topic of the book comprehensively, integrated waveguides, gratings, and optoelectronic power devices are included in addition Numerous elaborate illustrations promote an easy comprehension 'Integrated Silicon Optoelectronics'will be of value to engineers, physicists, and scientists in industry and at universities The book is also recommendable for graduate students speciali...
Latorre, Jose I
2015-01-01
There exists a remarkable four-qutrit state that carries absolute maximal entanglement in all its partitions. Employing this state, we construct a tensor network that delivers a holographic many body state, the H-code, where the physical properties of the boundary determine those of the bulk. This H-code is made of an even superposition of states whose relative Hamming distances are exponentially large with the size of the boundary. This property makes H-codes natural states for a quantum memory. H-codes exist on tori of definite sizes and get classified in three different sectors characterized by the sum of their qutrits on cycles wrapped through the boundaries of the system. We construct a parent Hamiltonian for the H-code which is highly non local and finally we compute the topological entanglement entropy of the H-code.
Takeuchi, Shingo
2013-01-01
We propose a holographic model of the SQUID (Superconducting QUantum Interference Device) composed of two Josephson junctions connected each other in a circle with the magnetic flux penetrating the circuit of the SQUID and the supercurrents flowing in both Josephson junction. The gravity in this paper is the Einstein-Maxwell-complex scalar field model on the four-dimensional Anti-de Sitter Schwarzschild black brane geometry in which one space direction is compactified into a circle, and we arrange the profile of the coefficient of the time component of the gauge field having the role for the chemical potential of the cooper pair. The magnetic flux is involved by the rewriting of the surface integral of the magnetic field to the contour integral of the gauge field.
Zhang, Jingfei; ZHANG Xin; Liu, Hongya
2007-01-01
We propose in this Letter a holographic model of tachyon dark energy. A connection between the tachyon scalar-field and the holographic dark energy is established, and accordingly, the potential of the holographic tachyon field is constructed. We show that the holographic evolution of the universe with $c\\geqslant 1$ can be described completely by the resulting tachyon model in a certain way.
Optoelectronics circuits manual
Marston, R M
2013-01-01
Optoelectronics Circuits Manual covers the basic principles and characteristics of the best known types of optoelectronic devices, as well as the practical applications of many of these optoelectronic devices. The book describes LED display circuits and LED dot- and bar-graph circuits and discusses the applications of seven-segment displays, light-sensitive devices, optocouplers, and a variety of brightness control techniques. The text also tackles infrared light-beam alarms and multichannel remote control systems. The book provides practical user information and circuitry and illustrations.
Integrated Silicon Optoelectronics
Zimmermann, Horst K
2010-01-01
Integrated Silicon Optoelectronics synthesizes topics from optoelectronics and microelectronics. The book concentrates on silicon as the major base of modern semiconductor devices and circuits. Starting from the basics of optical emission and absorption, as well as from the device physics of photodetectors, the aspects of the integration of photodetectors in modern bipolar, CMOS, and BiCMOS technologies are discussed. Detailed descriptions of fabrication technologies and applications of optoelectronic integrated circuits are included. The book, furthermore, contains a review of the newest state of research on eagerly anticipated silicon light emitters. In order to cover the topics comprehensively, also included are integrated waveguides, gratings, and optoelectronic power devices. Numerous elaborate illustrations facilitate and enhance comprehension. This extended edition will be of value to engineers, physicists, and scientists in industry and at universities. The book is also recommended to graduate student...
Steps towards silicon optoelectronics
Starovoytov, A
1999-01-01
nanostructure fabrication. Thus, this thesis makes a dual contribution to the chosen field: it summarises the present knowledge on the possibility of utilising optical properties of nanocrystalline silicon in silicon-based electronics, and it reports new results within the framework of the subject. The main conclusion is that due to its promising optoelectronic properties nanocrystalline silicon remains a prospective competitor for the cheapest and fastest microelectronics of the next century. This thesis addresses the issue of a potential future microelectronics technology, namely the possibility of utilising the optical properties of nanocrystalline silicon for optoelectronic circuits. The subject is subdivided into three chapters. Chapter 1 is an introduction. It formulates the oncoming problem for microelectronic development, explains the basics of Integrated Optoelectronics, introduces porous silicon as a new light-emitting material and gives a brief review of other competing light-emitting material syst...
Optoelectronic Mounting Structure
Energy Technology Data Exchange (ETDEWEB)
Anderson, Gene R. (Albuquerque, NM); Armendariz, Marcelino G. (Albuquerque, NM); Baca, Johnny R. F. (Albuquerque, NM); Bryan, Robert P. (Albuquerque, NM); Carson, Richard F. (Albuquerque, NM); Chu, Dahwey (Albuquerque, NM); Duckett, III, Edwin B. (Albuquerque, NM); McCormick, Frederick B. (Albuquerque, NM); Peterson, David W. (Sandia Park, NM); Peterson, Gary D. (Albuquerque, NM); Reber, Cathleen A. (Corrales, NM); Reysen, Bill H. (Lafayette, CO)
2004-10-05
An optoelectronic mounting structure is provided that may be used in conjunction with an optical transmitter, receiver or transceiver module. The mounting structure may be a flexible printed circuit board. Thermal vias or heat pipes in the head region may transmit heat from the mounting structure to the heat spreader. The heat spreader may provide mechanical rigidity or stiffness to the heat region. In another embodiment, an electrical contact and ground plane may pass along a surface of the head region so as to provide an electrical contact path to the optoelectronic devices and limit electromagnetic interference. In yet another embodiment, a window may be formed in the head region of the mounting structure so as to provide access to the heat spreader. Optoelectronic devices may be adapted to the heat spreader in such a manner that the devices are accessible through the window in the mounting structure.
Holographic entropy production
Tian, Yu; Wu, Xiao-Ning; Zhang, Hongbao
2014-10-01
The suspicion that gravity is holographic has been supported mainly by a variety of specific examples from string theory. In this paper, we propose that such a holography can actually be observed in the context of Einstein's gravity and at least a class of generalized gravitational theories, based on a definite holographic principle where neither is the bulk space-time required to be asymptotically AdS nor the boundary to be located at conformal infinity, echoing Wilson's formulation of quantum field theory. After showing the general equilibrium thermodynamics from the corresponding holographic dictionary, in particular, we provide a rather general proof of the equality between the entropy production on the boundary and the increase of black hole entropy in the bulk, which can be regarded as strong support to this holographic principle. The entropy production in the familiar holographic superconductors/superfluids is investigated as an important example, where the role played by the holographic renormalization is explained.
Holographic Entropy Production
Tian, Yu; Zhang, Hong-Bao
2014-01-01
The suspicion that gravity is holographic has been supported mainly by a variety of specific examples from string theory. In this paper, we propose that such a holography can actually be observed in the context of Einstein's gravity and at least a class of generalized gravitational theories, based on a definite holographic principle where neither is the bulk space-time required to be asymptotically AdS nor the boundary to be located at conformal infinity, echoing Wilson's formulation of quantum field theory. After showing the general equilibrium thermodynamics from the corresponding holographic dictionary, in particular, we provide a rather general proof of the equality between the entropy production on the boundary and the increase of black hole entropy in the bulk, which can be regarded as strong support to this holographic principle. The entropy production in the familiar holographic superconductors/superfluids is investigated as an important example, where the role played by the holographic renormalizatio...
Semiconductor opto-electronics
Moss, TS; Ellis, B
1972-01-01
Semiconductor Opto-Electronics focuses on opto-electronics, covering the basic physical phenomena and device behavior that arise from the interaction between electromagnetic radiation and electrons in a solid. The first nine chapters of this book are devoted to theoretical topics, discussing the interaction of electromagnetic waves with solids, dispersion theory and absorption processes, magneto-optical effects, and non-linear phenomena. Theories of photo-effects and photo-detectors are treated in detail, including the theories of radiation generation and the behavior of semiconductor lasers a
Optoelectronic packaging: A review
Energy Technology Data Exchange (ETDEWEB)
Carson, R.F.
1993-09-01
Optoelectronics and photonics hold great potential for high data-rate communication and computing. Wide using in computing applications was limited first by device technologies and now suffers due to the need for high-precision, mass-produced packaging. The use of phontons as a medium of communication and control implies a unique set of packaging constraints that was not present in traditional telecommunications applications. The state-of-the-art in optoelectronic packaging is now driven by microelectric techniques that have potential for low cost and high volume manufacturing.
Nanotube electronics and optoelectronics
Directory of Open Access Journals (Sweden)
Phaedon Avouris
2006-10-01
Full Text Available Among the many materials that have been proposed to supplement and, in the long run, possibly succeed Si as a basis for nanoelectronics, carbon nanotubes (CNTs have attracted the most attention. CNTs are quasi-one-dimensional materials with unique properties ideally suited for electronics. We briefly discuss the electrical and optical properties of CNTs and how they can be employed in electronics and optoelectronics. We focus on single CNT transistors, their fabrication, assembly, doping, electrical characteristics, and integration. We also address the possible use of CNTs in optoelectronic devices such as electroluminescent light emitters and photodetectors.
Nicotri, Stefano
2009-01-01
A holographic description of scalar mesons is presented, in which two- and three-point functions are holographically reconstructed. Mass spectrum, decay constants, eigenfunctions and the coupling of the scalar states with two pseu- doscalars are found. A comparison of the results with current phenomenology is discussed.
2013-03-07
DARPA NNI/NNCO BRI (2D Materials & Devices Beyond Graphene – planning phase) LRIR PIs Szep – RY: PICS Quantum Information...vertically from plasmonic filters into Si CMOS image sensor diodes via PMMA dielectric and SiNx vertical light couplers - •Designed and implemented signal...model) gernot.pomrenke@afosr.af.mil Future: Metasurfaces/ Meta Photonics, Quantum Integrated Nanophotonics, Ultra Low Power, Graphene Optoelectronics
Graphene Photonics and Optoelectronics
Bonaccorso, F.; Z. Sun; Hasan, T.; Ferrari, A. C.
2010-01-01
The richness of optical and electronic properties of graphene attracts enormous interest. Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability. So far, the main focus has been on fundamental physics and electronic devices. However, we believe its true potential to be in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, ...
Holographic Quantum Entanglement Negativity
Chaturvedi, Pankaj; Sengupta, Gautam
2016-01-01
We propose a holographic prescription to compute the entanglement negativity for conformal field theories at finite temperatures which exactly reproduces the entanglement negativity for (1+1)- dimensional conformal field theories at finite temperatures dual to (2+1)- dimensional bulk Euclidean BTZ black holes. We observe that the holographic entanglement negativity captures the distillable pure quantum entanglement and is related to the holographic mutual information. The application of our prescription to higher dimensional conformal field theories at finite temperatures within a $AdS_{d+1}/CFT_{d}$ scenario involving dual bulk $AdS$-Schwarzschild black holes is discussed to elucidate the universality of our conjecture.
Haque, S Shajidul
2016-01-01
We propose a simple and generic holographic $c$-function that is defined purely from geometry by using the non-affine expansion for null congruences. We examined the proposal for BPS black solutions in $\\mathcal{N}=2$ gauged supergravity that interpolate between two different dimensional AdS spacetimes and also for domain wall solutions. Moreover, we commented on the relation of this geometric proposal with the one from the holographic entanglement entropy.
Quantum-Holographic Informational Consciousness
National Research Council Canada - National Science Library
Francisco Di Biase
2009-01-01
The author propose a quantum-informational holographic model of brain-consciousness-universe interactions based in the holonomic neural networks of Karl Pribram, in the holographic quantum theory...
Miniaturized low-cost digital holographic interferometer
Michalkiewicz, Aneta; Kujawinska, Małgorzata; Marc, Paweł; Jaroszewicz, Leszek R.
2006-04-01
Digital holography (DH) and digital holographic interferometry (DHI) are very useful, robust, full-field visualization and measurement techniques applied for small objects, especially in the field of bioengineering and microelements system testing. Nowadays CCD/CMOS detectors and microlasers allow to build miniaturized and compact digital holographic head. Various approaches to develop DH/DHI systems including a variety of optical and mechanical solutions have been made. The main recent requirements for holocamera design include compactness, insensitivity to vibrations environmental changes and with good quality of output data. Other requirement is the ability to build a low-cost and robust system for sensing applications. In our paper, we propose a design of miniaturized holo-camera head with fibre optics light delivery system and remote data read-out. The opto-mechanical architecture allows out-of-plane and shape measurements of diffuse and reflective surfaces. The possible data capture schemes and software for enhanced quality numerical reconstruction of complex objects are discussed and the optimized methodology is determined. Also real-time optoelectronic hologram reconstruction is demonstrated on the base of remote data delivery to liquid crystal on silicon spatial light modulator. The performance of the system is tested on the resolution amplitude test and master sphere, while engineering objects in the experiments are static and dynamic microelements.
Materials for optoelectronic devices
Energy Technology Data Exchange (ETDEWEB)
Shiang, Joseph John; Smigelski, Jr., Paul Michael
2015-01-27
Energy efficient optoelectronic devices include an electroluminescent layer containing a polymer made up of structural units of formula I and II; ##STR00001## wherein R.sup.1 and R.sup.2 are independently C.sub.22-44 hydrocarbyl, C.sub.22-44 hydrocarbyl containing one or more S, N, O, P, or Si atoms, oxaalkylaryl, or a combination thereof; R.sup.3 and R.sup.4 are independently H, C.sub.1-44 hydrocarbyl or C.sub.1-44 hydrocarbyl containing one or more S, N, O, P, or Si atoms, or R.sup.3 and R.sup.4, taken together, form a C.sub.2-10 monocyclic or bicyclic ring containing up to three S, N, O, P, or Si heteroatoms; and X is S, Se, or a combination thereof.
Integrated terahertz optoelectronics
Liang, Guozhen; Wang, Qi Jie
2016-11-01
Currently, terahertz (THz) optical systems are based on bulky free-space optics. This is due to the lack of a common platform onto which different THz components, e.g., source, waveguide, modulator and detector, can be monolithically integrated. With the development of THz quantum cascade laser (QCL), it has been realized that the QCL chip may be such a platform for integrated THz photonics. Here, we report our recent works where the THz QCL is integrated with passive or optoelectronic components. They are: 1) integrated graphene modulator with THz QCL achieving 100% modulation depth and fast speed; 2) phase-locked THz QCL with integrated plasmonic waveguide and subwavelength antennas realizing dynamically widely tunable polarizations.
Khitun, Alexander; Kozhevnikov, Alexander; Gertz, Frederick; Filimonov, Yuri
2015-03-01
Collective oscillation of spins in magnetic lattice known as spin waves (magnons) possess relatively long coherence length at room temperature, which makes it possible to build sub-micrometer scale holographic devices similar to the devices developed in optics. In this work, we present a prototype 2-bit magnonic holographic memory. The memory consists of the double-cross waveguide structure made of Y3Fe2(FeO4)3 with magnets placed on the top of waveguide junctions. Information is encoded in the orientation of the magnets, while the read-out is accomplished by the spin waves generated by the micro-antennas placed on the edges of the waveguides. The interference pattern produced by multiple spin waves makes it possible to build a unique holographic image of the magnetic structure and recognize the state of the each magnet. The development of magnonic holographic devices opens a new horizon for building scalable holographic devices compatible with conventional electronic devices. This work was supported in part by the FAME Center, one of six centers of STARnet, a Semiconductor Research Corporation program sponsored by MARCO and DARPA and by the National Science Foundation under the NEB2020 Grant ECCS-1124714.
Holographic Spherically Symmetric Metrics
Petri, Michael
The holographic principle (HP) conjectures, that the maximum number of degrees of freedom of any realistic physical system is proportional to the system's boundary area. The HP has its roots in the study of black holes. It has recently been applied to cosmological solutions. In this article we apply the HP to spherically symmetric static space-times. We find that any regular spherically symmetric object saturating the HP is subject to tight constraints on the (interior) metric, energy-density, temperature and entropy-density. Whenever gravity can be described by a metric theory, gravity is macroscopically scale invariant and the laws of thermodynamics hold locally and globally, the (interior) metric of a regular holographic object is uniquely determined up to a constant factor and the interior matter-state must follow well defined scaling relations. When the metric theory of gravity is general relativity, the interior matter has an overall string equation of state (EOS) and a unique total energy-density. Thus the holographic metric derived in this article can serve as simple interior 4D realization of Mathur's string fuzzball proposal. Some properties of the holographic metric and its possible experimental verification are discussed. The geodesics of the holographic metric describe an isotropically expanding (or contracting) universe with a nearly homogeneous matter-distribution within the local Hubble volume. Due to the overall string EOS the active gravitational mass-density is zero, resulting in a coasting expansion with Ht = 1, which is compatible with the recent GRB-data.
Deformable paper origami optoelectronic devices
He, Jr-Hau
2017-01-19
Deformable optoelectronic devices are provided, including photodetectors, photodiodes, and photovoltaic cells. The devices can be made on a variety of paper substrates, and can include a plurality of fold segments in the paper substrate creating a deformable pattern. Thin electrode layers and semiconductor nanowire layers can be attached to the substrate, creating the optoelectronic device. The devices can be highly deformable, e.g. capable of undergoing strains of 500% or more, bending angles of 25° or more, and/or twist angles of 270° or more. Methods of making the deformable optoelectronic devices and methods of using, e.g. as a photodetector, are also provided.
Talbot, Michael
1991-01-01
'There is evidence to suggest that our world and everything in it - from snowflakes to maple trees to falling stars and spinning electrons - are only ghostly images, projections from a level of reality literally beyond both space and time.' This is the astonishing idea behind the holographic theory of the universe, pioneered by two eminent thinkers: physicist David Bohm, a former protege of Albert Einstein, and quantum physicist Karl Pribram. The holographic theory of the universe encompasses consciousness and reality as we know them, but can also explain such hitherto unexplained phenomena as telepathy, out-of-body experiences and even miraculous healing. In this remarkable book, Michael Talbot reveals the extraordinary depth and power of the holographic theory of the universe, illustrating how it makes sense of the entire range of experiences within our universe - and in other universes beyond our own.
Wang, Shuang; Li, Miao
2016-01-01
We review the paradigm of holographic dark energy (HDE), which arises from a theoretical attempt of applying the holographic principle (HP) to the dark energy (DE) problem. Making use of the HP and the dimensional analysis, we derive the general formula of the energy density of HDE. Then, we describe the properties of HDE model, in which the future event horizon is chosen as the characteristic length scale. We also introduce the theoretical explorations and the observational constraints for this model. Next, in the framework of HDE, we discuss various topics, such as spatial curvature, neutrino, instability of perturbation, time-varying gravitational constant, inflation, black hole and big rip singularity. In addition, from both the theoretical and the observational aspects, we introduce the interacting holographic dark energy scenario, where the interaction between dark matter and HDE is taken into account. Furthermore, we discuss the HDE scenario in various modified gravity (MG) theories, such as Brans-Dick...
Holographic Entanglement Entropy
Rangamani, Mukund
2016-01-01
We review the developments in the past decade on holographic entanglement entropy, a subject that has garnered much attention owing to its potential to teach us about the emergence of spacetime in holography. We provide an introduction to the concept of entanglement entropy in quantum field theories, review the holographic proposals for computing the same, providing some justification for where these proposals arise from in the first two parts. The final part addresses recent developments linking entanglement and geometry. We provide an overview of the various arguments and technical developments that teach us how to use field theory entanglement to detect geometry. Our discussion is by design eclectic; we have chosen to focus on developments that appear to us most promising for further insights into the holographic map. This is a preliminary draft of a few chapters of a book which will appear sometime in the near future, to be published by Springer. The book in addition contains a discussion of application o...
Phenomenology of Holographic Quenches
da Silva, Emilia; Lopez, Esperanza; Mas, Javier; Serantes, Alexandre
2015-10-01
We study holographic models related to global quantum quenches in finite size systems. The holographic set up describes naturally a CFT, which we consider on a circle and a sphere. The enhanced symmetry of the conformal group on the circle motivates us to compare the evolution in both cases. Depending on the initial conditions, the dual geometry exhibits oscillations that we holographically interpret as revivals of the initial field theory state. On the sphere, this only happens when the energy density created by the quench is small compared to the system size. However on the circle considerably larger energy densities are compatible with revivals. Two different timescales emerge in this latter case. A collapse time, when the system appears to have dephased, and the revival time, when after rephasing the initial state is partially recovered. The ratio of these two times depends upon the initial conditions in a similar way to what is observed in some experimental setups exhibiting collapse and revivals.
Brehm, Enrico M
2016-01-01
In this work, we introduce classical holographic codes. These can be understood as concatenated probabilistic codes and can be represented as networks uniformly covering hyperbolic space. In particular, classical holographic codes can be interpreted as maps from bulk degrees of freedom to boundary degrees of freedom. Interestingly, they are shown to exhibit features similar to those expected from the AdS/CFT correspondence. Among these are a version of the Ryu-Takayanagi formula and intriguing properties regarding bulk reconstruction and boundary representations of bulk operations. We discuss the relation of our findings with expectations from AdS/CFT and, in particular, with recent results from quantum error correction.
Holographic microrheology of biofilms
Chiong Cheong, Fook; Duarte, Simone; Grier, David
2008-03-01
We present microrheological measurements of polymeric matrices, including the extra-cellular polysaccharide gel synthesized by the dental pathogen S. mutans. As part of this study, we introduce the use of precision three-dimensional particle tracking based on video holographic microscopy. This technique offers nanometer-scale resolution at video rates, thereby providing detailed information on the gels' complex viscoelastic moduli, including insights into their heterogeneity. The particular application to dental biofilms complements previous studies based on macroscopic rheology, and demonstrates the utility of holographic microrheology for soft-matter physics and biomedical research.
Ultrafast Graphene Photonics and Optoelectronics
2017-04-14
structures that consist of a sheet of graphene and a plasma substrate such as a metal, a doped semiconductor, or another graphene layer. Using these...AFRL-AFOSR-JP-TR-2017-0032 Ultrafast Graphene Photonics and Optoelectronics Kuang-Hsiung Wu National Chiao Tung University Final Report 04/14/2017...DATES COVERED (From - To) 18 Apr 2013 to 17 Apr 2016 4. TITLE AND SUBTITLE Ultrafast Graphene Photonics and Optoelectronics 5a. CONTRACT NUMBER 5b
Reconfigurable Integrated Optoelectronics
Directory of Open Access Journals (Sweden)
Richard Soref
2011-01-01
Full Text Available Integrated optics today is based upon chips of Si and InP. The future of this chip industry is probably contained in the thrust towards optoelectronic integrated circuits (OEICs and photonic integrated circuits (PICs manufactured in a high-volume foundry. We believe that reconfigurable OEICs and PICs, known as ROEICs and RPICs, constitute the ultimate embodiment of integrated photonics. This paper shows that any ROEIC-on-a-chip can be decomposed into photonic modules, some of them fixed and some of them changeable in function. Reconfiguration is provided by electrical control signals to the electro-optical building blocks. We illustrate these modules in detail and discuss 3D ROEIC chips for the highest-performance signal processing. We present examples of our module theory for RPIC optical lattice filters already constructed, and we propose new ROEICs for directed optical logic, large-scale matrix switching, and 2D beamsteering of a phased-array microwave antenna. In general, large-scale-integrated ROEICs will enable significant applications in computing, quantum computing, communications, learning, imaging, telepresence, sensing, RF/microwave photonics, information storage, cryptography, and data mining.
Holographic analysis of photopolymers
Sullivan, Amy C.; Alim, Marvin D.; Glugla, David J.; McLeod, Robert R.
2017-05-01
Two-beam holographic exposure and subsequent monitoring of the time-dependent first-order Bragg diffraction is a common method for investigating the refractive index response of holographic photopolymers for a range of input writing conditions. The experimental set up is straightforward, and Kogelnik's well-known coupled wave theory (CWT)[1] can be used to separate measurements of the change in index of refraction (Δn) and the thickness of transmission and reflection holograms. However, CWT assumes that the hologram is written and read out with a plane wave and that the hologram is uniform in both the transverse and depth dimensions, assumptions that are rarely valid in practical holographic testing. The effect of deviations from these assumptions on the measured thickness and Δn become more pronounced for over-modulated exposures. As commercial and research polymers reach refractive index modulations on the order of 10-2, even relatively thin (refractive index in a material system. We use this analysis to study a model high Δn two-stage photopolymer holographic material using both transmission and reflection holograms.
Holographic renormalization and supersymmetry
Genolini, Pietro Benetti; Cassani, Davide; Martelli, Dario; Sparks, James
2017-02-01
Holographic renormalization is a systematic procedure for regulating divergences in observables in asymptotically locally AdS spacetimes. For dual boundary field theories which are supersymmetric it is natural to ask whether this defines a supersymmetric renormalization scheme. Recent results in localization have brought this question into sharp focus: rigid supersymmetry on a curved boundary requires specific geometric structures, and general arguments imply that BPS observables, such as the partition function, are invariant under certain deformations of these structures. One can then ask if the dual holographic observables are similarly invariant. We study this question in minimal N = 2 gauged supergravity in four and five dimensions. In four dimensions we show that holographic renormalization precisely reproduces the expected field theory results. In five dimensions we find that no choice of standard holographic counterterms is compatible with supersymmetry, which leads us to introduce novel finite boundary terms. For a class of solutions satisfying certain topological assumptions we provide some independent tests of these new boundary terms, in particular showing that they reproduce the expected VEVs of conserved charges.
Heterodyned holographic spectroscopy
Douglas, NG
1997-01-01
In holographic spectroscopy an image of an interference pattern is projected onto a detector and transformed back to the input spectrum. The general characteristics are similar to those of Fourier transform spectroscopy, but the spectrum is obtained without scanning. In the heterodyned arrangement o
A Holographic Bound for D3-Brane
Momeni, Davood; Bahamonde, Sebastian; Myrzakul, Aizhan; Myrzakulov, Ratbay
2016-01-01
In this paper, we will calculate the holographic entanglement entropy, holographic complexity, and fidelity susceptibility for a D3-brane. It will be demonstrated that for a D3-brane the holographic complexity is always greater than or equal to than the fidelity susceptibility. Furthermore, we will also demonstrate that the holographic complexity is related to the holographic entanglement entropy for this system. Thus, we will obtain a holographic bound involving holographic complexity, holographic entanglement entropy and fidelity susceptibility of a D3-brane.
Energy Technology Data Exchange (ETDEWEB)
Liu Jifeng, E-mail: Jifeng.Liu@Dartmouth.edu [Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 (United States); Camacho-Aguilera, Rodolfo; Bessette, Jonathan T.; Sun, Xiaochen [Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Wang Xiaoxin [Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 (United States); Cai Yan; Kimerling, Lionel C.; Michel, Jurgen [Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)
2012-02-01
Electronic-photonic synergy has become an increasingly clear solution to enhance the bandwidth and improve the energy efficiency of information systems. Monolithic integration of optoelectronic devices is the ideal solution for large-scale electronic-photonic synergy. Due to its pseudo-direct gap behavior in optoelectronic properties and compatibility with Si electronics, epitaxial Ge-on-Si has become an attractive solution for monolithic optoelectronics. In this paper we will review recent progress in Ge-on-Si optoelectronics, including photodetectors, electroabsorption modulators, and lasers. The performance of these devices has been enhanced by band-engineering such as tensile strain and n-type doping, which transforms Ge towards a direct gap material. Selective growth reduces defect density and facilitates monolithic integration at the same time. Ge-on-Si photodetectors have approached or exceeded the performance of their III-V counterparts, with bandwidth-efficiency product > 30 GHz for p-i-n photodiodes and bandwidth-gain product > 340 GHz for avalanche photodiodes. Enhanced Franz-Keldysh effect in tensile-strained Ge offers ultralow energy photonic modulation with < 30 fJ/bit energy consumption and > 100 GHz intrinsic bandwidth. Room temperature optically-pumped lasing as well as electroluminescence has also been achieved from the direct gap transition of band-engineered Ge-on-Si waveguides. These results indicate that band-engineered Ge-on-Si is promising to achieve monolithic active optoelectronic devices on a Si platform.
Intelligent holographic databases
Barbastathis, George
Memory is a key component of intelligence. In the human brain, physical structure and functionality jointly provide diverse memory modalities at multiple time scales. How could we engineer artificial memories with similar faculties? In this thesis, we attack both hardware and algorithmic aspects of this problem. A good part is devoted to holographic memory architectures, because they meet high capacity and parallelism requirements. We develop and fully characterize shift multiplexing, a novel storage method that simplifies disk head design for holographic disks. We develop and optimize the design of compact refreshable holographic random access memories, showing several ways that 1 Tbit can be stored holographically in volume less than 1 m3, with surface density more than 20 times higher than conventional silicon DRAM integrated circuits. To address the issue of photorefractive volatility, we further develop the two-lambda (dual wavelength) method for shift multiplexing, and combine electrical fixing with angle multiplexing to demonstrate 1,000 multiplexed fixed holograms. Finally, we propose a noise model and an information theoretic metric to optimize the imaging system of a holographic memory, in terms of storage density and error rate. Motivated by the problem of interfacing sensors and memories to a complex system with limited computational resources, we construct a computer game of Desert Survival, built as a high-dimensional non-stationary virtual environment in a competitive setting. The efficacy of episodic learning, implemented as a reinforced Nearest Neighbor scheme, and the probability of winning against a control opponent improve significantly by concentrating the algorithmic effort to the virtual desert neighborhood that emerges as most significant at any time. The generalized computational model combines the autonomous neural network and von Neumann paradigms through a compact, dynamic central representation, which contains the most salient features
Deriving covariant holographic entanglement
Dong, Xi; Lewkowycz, Aitor; Rangamani, Mukund
2016-11-01
We provide a gravitational argument in favour of the covariant holographic entanglement entropy proposal. In general time-dependent states, the proposal asserts that the entanglement entropy of a region in the boundary field theory is given by a quarter of the area of a bulk extremal surface in Planck units. The main element of our discussion is an implementation of an appropriate Schwinger-Keldysh contour to obtain the reduced density matrix (and its powers) of a given region, as is relevant for the replica construction. We map this contour into the bulk gravitational theory, and argue that the saddle point solutions of these replica geometries lead to a consistent prescription for computing the field theory Rényi entropies. In the limiting case where the replica index is taken to unity, a local analysis suffices to show that these saddles lead to the extremal surfaces of interest. We also comment on various properties of holographic entanglement that follow from this construction.
Deriving covariant holographic entanglement
Dong, Xi; Rangamani, Mukund
2016-01-01
We provide a gravitational argument in favour of the covariant holographic entanglement entropy proposal. In general time-dependent states, the proposal asserts that the entanglement entropy of a region in the boundary field theory is given by a quarter of the area of a bulk extremal surface in Planck units. The main element of our discussion is an implementation of an appropriate Schwinger-Keldysh contour to obtain the reduced density matrix (and its powers) of a given region, as is relevant for the replica construction. We map this contour into the bulk gravitational theory, and argue that the saddle point solutions of these replica geometries lead to a consistent prescription for computing the field theory Renyi entropies. In the limiting case where the replica index is taken to unity, a local analysis suffices to show that these saddles lead to the extremal surfaces of interest. We also comment on various properties of holographic entanglement that follow from this construction.
Vorticity in holographic fluids
Caldarelli, Marco M; Petkou, Anastasios C; Petropoulos, P Marios; Pozzoli, Valentina; Siampos, Konstadinos
2012-01-01
In view of the recent interest in reproducing holographically various properties of conformal fluids, we review the issue of vorticity in the context of AdS/CFT. Three-dimensional fluids with vorticity require four-dimensional bulk geometries with either angular momentum or nut charge, whose boundary geometries fall into the Papapetrou--Randers class. The boundary fluids emerge in stationary non-dissipative kinematic configurations, which can be cyclonic or vortex flows, evolving in compact or non-compact supports. A rich network of Einstein's solutions arises, naturally connected with three-dimensional Bianchi spaces. We use Fefferman--Graham expansion to handle holographic data from the bulk and discuss the alternative for reversing the process and reconstruct the exact bulk geometries.
An introduction to optoelectronic sensors
Tajani, Antonella; Cutolo, Antonello
2009-01-01
This invaluable book offers a comprehensive overview of the technologies and applications of optoelectronic sensors. Based on the R&D experience of more than 70 engineers and scientists, highly representative of the Italian academic and industrial community in this area, this book provides a broad and accurate description of the state-of-the-art optoelectronic technologies for sensing. The most innovative approaches, such as the use of photonic crystals, squeezed states of light and microresonators for sensing, are considered. Application areas range from environment to medicine and healthcare
Luminet, Jean-Pierre
2016-01-01
I give a critical review of the holographic hypothesis, which posits that a universe with gravity can be described by a quantum field theory in fewer dimensions. I first recall how the idea originated from considerations on black hole thermodynamics and the so-called information paradox that arises when Hawking radiation is taken into account. String Quantum Gravity tried to solve the puzzle using the AdS/CFT correspondence, according to which a black hole in a 5-D anti-de Sitter space is like a flat 4-D field of particles and radiation. Although such an interesting holographic property, also called gauge/gravity duality, has never been proved rigorously, it has impulsed a number of research programs in fields as diverse as nuclear physics, condensed matter physics, general relativity and cosmology. I finally discuss the pros and cons of the holographic conjecture, and emphasizes the key role played by black holes for understanding quantum gravity and possible dualities between distant fields of theoretical p...
Holographic entanglement entropy
Rangamani, Mukund
2017-01-01
This book provides a comprehensive overview of developments in the field of holographic entanglement entropy. Within the context of the AdS/CFT correspondence, it is shown how quantum entanglement is computed by the area of certain extremal surfaces. The general lessons one can learn from this connection are drawn out for quantum field theories, many-body physics, and quantum gravity. An overview of the necessary background material is provided together with a flavor of the exciting open questions that are currently being discussed. The book is divided into four main parts. In the first part, the concept of entanglement, and methods for computing it, in quantum field theories is reviewed. In the second part, an overview of the AdS/CFT correspondence is given and the holographic entanglement entropy prescription is explained. In the third part, the time-dependence of entanglement entropy in out-of-equilibrium systems, and applications to many body physics are explored using holographic methods. The last part f...
Holographic predictions for cosmological 3-point functions
Bzowski, A.; McFadden, P.; Skenderis, K.
2012-01-01
We present the holographic predictions for cosmological 3-point correlators, involving both scalar and tensor modes, for a universe which started in a non-geometric holographic phase. Holographic formulae relate the cosmological 3-point functions to stress tensor correlation functions of a holograph
Laser addressed holographic memory system
Gange, R. A.; Wagle, E. M.; Steinmetz, C. C.
1973-01-01
Holographic recall and storage system uses red-lipid microcrystalline wax as storage medium. When laser beam strikes wax, its energy heats point of incidence enough to pass wax through transition temperature. Holograph image can then be written or erased in softened wax.
Simple Optoelectronic Feedback in Microwave Oscillators
Maleki, Lute; Iltchenko, Vladimir
2009-01-01
A proposed method of stabilizing microwave and millimeter-wave oscillators calls for the use of feedback in optoelectronic delay lines characterized by high values of the resonance quality factor (Q). The method would extend the applicability of optoelectronic feedback beyond the previously reported class of optoelectronic oscillators that comprise two-port electronic amplifiers in closed loops with high-Q feedback circuits.
An optoelectronic fuel level sensor
Murashkina, T. I.; Badeeva, E. A.; Badeev, A. V.; Savochkina, M. M.
2017-01-01
The block and schematic construction diagrams of a new optoelectronic fuel level sensor are considered. The operating principle of the sensor is based on registering the intensity value of the optical path reflected from the mirror, located on the reservoir bottom.
A holographic bound for D3-brane
Energy Technology Data Exchange (ETDEWEB)
Momeni, Davood; Myrzakul, Aizhan; Myrzakulov, Ratbay [Eurasian National University, Eurasian International Center for Theoretical Physics, Astana (Kazakhstan); Eurasian National University, Department of General Theoretical Physics, Astana (Kazakhstan); Faizal, Mir [University of British Columbia-Okanagan, Irving K. Barber School of Arts and Sciences, Kelowna, BC (Canada); University of Lethbridge, Department of Physics and Astronomy, Lethbridge, AB (Canada); Bahamonde, Sebastian [University College London, Department of Mathematics, London (United Kingdom)
2017-06-15
In this paper, we will regularize the holographic entanglement entropy, holographic complexity and fidelity susceptibility for a configuration of D3-branes. We will also study the regularization of the holographic complexity from the action for a configuration of D3-branes. It will be demonstrated that for a spherical shell of D3-branes the regularized holographic complexity is always greater than or equal to the regularized fidelity susceptibility. Furthermore, we will also demonstrate that the regularized holographic complexity is related to the regularized holographic entanglement entropy for this system. Thus, we will obtain a holographic bound involving regularized holographic complexity, regularized holographic entanglement entropy and regularized fidelity susceptibility of a configuration of D3-brane. We will also discuss a bound for regularized holographic complexity from action, for a D3-brane configuration. (orig.)
Telemedicine optoelectronic biomedical data processing system
Prosolovska, Vita V.
2010-08-01
The telemedicine optoelectronic biomedical data processing system is created to share medical information for the control of health rights and timely and rapid response to crisis. The system includes the main blocks: bioprocessor, analog-digital converter biomedical images, optoelectronic module for image processing, optoelectronic module for parallel recording and storage of biomedical imaging and matrix screen display of biomedical images. Rated temporal characteristics of the blocks defined by a particular triggering optoelectronic couple in analog-digital converters and time imaging for matrix screen. The element base for hardware implementation of the developed matrix screen is integrated optoelectronic couples produced by selective epitaxy.
Holographic interference filters
Diehl, Damon W.
Holographic mirrors have wavelength-selection properties and thus qualify as a class of interference filters. Two theoretical methods for analyzing such structures are developed. The first method uses Hill's matrix method to yield closed-forms solutions in terms of the Floquet-Bloch waves within a periodic structure. A process is developed for implementing this solution method on a computer, using sparse-matrix memory allocation, numerical root-finding algorithms, and inverse-iteration techniques. It is demonstrated that Hill's matrix method is valid for the analysis of finite and multi-periodic problems. The second method of theoretical analysis is a transfer-matrix technique, which is herein termed thin-film decomposition. It is shown that the two methods of solution yield results that differ by, at worst, a fraction of a percent. Using both calculation techniques, a number of example problems are explored. Of key importance is the construction of a set of curves that are useful for the design and characterization of holographic interference filters. In addition to the theoretical development, methods are presented for the fabrication of holographic interference filters using DuPont HRF-800X001 photopolymer. Central to the exposure system is a frequency-stabilized, tunable dye laser. The types of filters fabricated include single-tone reflection filters, two types of multitone reflection filters, and reflection filters for infrared wavelengths. These filters feature index profiles that are not easily attainable through other fabrication methods. As a supplement to the body of the dissertation, the computer algorithms developed to implement Hill's matrix method and thin-film decomposition are also included as an appendix. Further appendices provide more information on Floquet's theorem and Hill's matrix method. A final appendix presents a design for an infrared laser spectrophotometer.
Triple Encrypted Holographic Storage and Digital Holographic System
Institute of Scientific and Technical Information of China (English)
ZHU Yi-Chao; ZHANG Jia-Sen; GONG Qi-Huang
2008-01-01
We propose a triple encrypted holographic memory containing a digital holographic system. The original image is encrypted using double random phase encryption and stored in a LiNbO3:Fe crystal with shift-multiplexing. Both the reference beams of the memory and the digital holographic system are random phase encoded. We theoretically and experimentally demonstrate the encryption and decryption of multiple images and the results show high quality and good fault tolerance. The total key length of this system is larger than 4.7×1033.
Holographic Magnetisation Density Waves
Donos, Aristomenis
2016-01-01
We numerically construct asymptotically $AdS$ black brane solutions of $D=4$ Einstein theory coupled to a scalar and two $U(1)$ gauge fields. The solutions are holographically dual to $d=3$ CFTs in a constant external magnetic field along one of the $U(1)$'s. Below a critical temperature the system's magnetisation density becomes inhomogeneous, leading to spontaneous formation of current density waves. We find that the transition can be of second order and that the solutions which minimise the free energy locally in the parameter space of solutions have averaged stressed tensor of a perfect fluid.
Holographic charge density waves
Donos, Aristomenis
2013-01-01
We show that strongly coupled holographic matter at finite charge density can exhibit charge density wave phases which spontaneously break translation invariance while preserving time-reversal and parity invariance. We show that such phases are possible within Einstein-Maxwell-dilaton theory in general spacetime dimensions. We also discuss related spatially modulated phases when there is an additional coupling to a second vector field, possibly with non-zero mass. We discuss how these constructions, and others, should be associated with novel spatially modulated ground states.
Holographic charge density waves
Donos, Aristomenis; Gauntlett, Jerome P.
2013-06-01
We show that strongly coupled holographic matter at finite charge density can exhibit charge density wave phases which spontaneously break translation invariance while preserving time-reversal and parity invariance. We show that such phases are possible within Einstein-Maxwell-dilaton theory in general spacetime dimensions. We also discuss related spatially modulated phases when there is an additional coupling to a second vector field, possibly with nonzero mass. We discuss how these constructions, and others, should be associated with novel spatially modulated ground states.
Holographic effective field theories
Energy Technology Data Exchange (ETDEWEB)
Martucci, Luca [Dipartimento di Fisica ed Astronomia “Galileo Galilei' , Università di Padova,and INFN - Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy); Zaffaroni, Alberto [Dipartimento di Fisica, Università di Milano-Bicocca,and INFN - Sezione di Milano-Bicocca, I-20126 Milano (Italy)
2016-06-28
We derive the four-dimensional low-energy effective field theory governing the moduli space of strongly coupled superconformal quiver gauge theories associated with D3-branes at Calabi-Yau conical singularities in the holographic regime of validity. We use the dual supergravity description provided by warped resolved conical geometries with mobile D3-branes. Information on the baryonic directions of the moduli space is also obtained by using wrapped Euclidean D3-branes. We illustrate our general results by discussing in detail their application to the Klebanov-Witten model.
Explaining Holographic Dark Energy
Directory of Open Access Journals (Sweden)
Shan Gao
2013-10-01
Full Text Available The possible holographic origin of dark energy is investigated. The main existing explanations, namely the UV/IR connection argument of Cohen et al., Thomas’ bulk holography argument, and Ng’s spacetime foam argument, are shown to be not wholly satisfactory. A new explanation is then proposed based on the ideas of Thomas and Ng. It is suggested that dark energy originates from the quantum fluctuations of spacetime limited by the event horizon of the universe. Several potential problems of the explanation are also discussed.
Holographic quantum computing.
Tordrup, Karl; Negretti, Antonio; Mølmer, Klaus
2008-07-25
We propose to use a single mesoscopic ensemble of trapped polar molecules for quantum computing. A "holographic quantum register" with hundreds of qubits is encoded in collective excitations with definite spatial phase variations. Each phase pattern is uniquely addressed by optical Raman processes with classical optical fields, while one- and two-qubit gates and qubit readout are accomplished by transferring the qubit states to a stripline microwave cavity field and a Cooper pair box where controllable two-level unitary dynamics and detection is governed by classical microwave fields.
Geller, Michael; Telem, Ofri
2015-05-15
We present the first realization of a "twin Higgs" model as a holographic composite Higgs model. Uniquely among composite Higgs models, the Higgs potential is protected by a new standard model (SM) singlet elementary "mirror" sector at the sigma model scale f and not by the composite states at m_{KK}, naturally allowing for m_{KK} beyond the LHC reach. As a result, naturalness in our model cannot be constrained by the LHC, but may be probed by precision Higgs measurements at future lepton colliders, and by direct searches for Kaluza-Klein excitations at a 100 TeV collider.
A wideband sensitive holographic photopolymer
Institute of Scientific and Technical Information of China (English)
Mingju Huang; Sulian Wang; Airong Wang; Qiaoxia Gong; Fuxi Gan
2005-01-01
A novel wideband sensitive dry holographic photopolymer sensitized by rose bengal (RB) and methylene blue (MB) is fabricated, the holographic storage characteristics of which are investigated under different exposure wavelengths. The result shows that the sensitive spectral band exceeds 200 nm in visible light range, the maximum diffraction efficiency under different exposure wavelengths is more than 40% and decreases with the decrease of exposure wavelength, the exposure sensitivity is not change with the exposure wavelength.This photopolymer is appropriate for wavelength multiplexing or multi-wavelength recording in digital holographic storage.
Introduction to Holographic Superconductor Models
Cai, Rong-Gen; Li, Li-Fang; Yang, Run-Qiu
2015-01-01
In the last years it has been shown that some properties of strongly coupled superconductors can be potentially described by classical general relativity living in one higher dimension, which is known as holographic superconductors. This paper gives a quick and introductory overview of some holographic superconductor models with s-wave, p-wave and d-wave orders in the literature from point of view of bottom-up, and summarizes some basic properties of these holographic models in various regimes. The competition and coexistence of these superconductivity orders are also studied in these superconductor models.
Mid-infrared Semiconductor Optoelectronics
Krier, Anthony
2006-01-01
The practical realisation of optoelectronic devices operating in the 2–10 µm (mid-infrared) wavelength range offers potential applications in a variety of areas from environmental gas monitoring around oil rigs and landfill sites to the detection of pharmaceuticals, particularly narcotics. In addition, an atmospheric transmission window exists between 3 µm and 5 µm that enables free-space optical communications, thermal imaging applications and the development of infrared measures for "homeland security". Consequently, the mid-infrared is very attractive for the development of sensitive optical sensor instrumentation. Unfortunately, the nature of the likely applications dictates stringent requirements in terms of laser operation, miniaturisation and cost that are difficult to meet. Many of the necessary improvements are linked to a better ability to fabricate and to understand the optoelectronic properties of suitable high-quality epitaxial materials and device structures. Substantial progress in these m...
III-Nitride nanowire optoelectronics
Zhao, Songrui; Nguyen, Hieu P. T.; Kibria, Md. G.; Mi, Zetian
2015-11-01
Group-III nitride nanowire structures, including GaN, InN, AlN and their alloys, have been intensively studied in the past decade. Unique to this material system is that its energy bandgap can be tuned from the deep ultraviolet (~6.2 eV for AlN) to the near infrared (~0.65 eV for InN). In this article, we provide an overview on the recent progress made in III-nitride nanowire optoelectronic devices, including light emitting diodes, lasers, photodetectors, single photon sources, intraband devices, solar cells, and artificial photosynthesis. The present challenges and future prospects of III-nitride nanowire optoelectronic devices are also discussed.
Hopwood, Anthony I.
1991-10-01
This paper discusses a new type of holographic overlay, FLASHPRINT, which may be used in both security and packaging applications. Unlike the more common embossed holograms currently used, FLASHPRINT leads to reduced set-up costs and offers a simpler process. This reduces the long lead times characteristic of the existing technology and requires the customer to provide only two-dimensional artwork. The overlay material contains a covert 2-D image. The image may be switched on or off by simply tilting the overlay in a light source. The overlay is replayed in the 'on' position to reveal the encoded security message as a highly saturated gold colored image. This effect is operable for a wide range of lighting conditions and viewing geometries. In the 'off' position the overlay is substantially transparent. These features make the visual effect of the overlay attractive to incorporate into product design. They may be laminated over complex printed artwork such as labels and security passes without masking the printed message. When switched 'on' the image appears both sharp and more than seven times brighter than white paper. The image remains sharp and clear even in less favorable lighting conditions. Although the technique offers a low set-up cost for the customer, through its simplicity, it remains as technically demanding and difficult to counterfeit as any holographic process.
The traveltime holographic principle
Huang, Y.
2014-11-06
Fermat\\'s interferometric principle is used to compute interior transmission traveltimes τpq from exterior transmission traveltimes τsp and τsq. Here, the exterior traveltimes are computed for sources s on a boundary B that encloses a volume V of interior points p and q. Once the exterior traveltimes are computed, no further ray tracing is needed to calculate the interior times τpq. Therefore this interferometric approach can be more efficient than explicitly computing interior traveltimes τpq by ray tracing. Moreover, the memory requirement of the traveltimes is reduced by one dimension, because the boundary B is of one fewer dimension than the volume V. An application of this approach is demonstrated with interbed multiple (IM) elimination. Here, the IMs in the observed data are predicted from the migration image and are subsequently removed by adaptive subtraction. This prediction is enabled by the knowledge of interior transmission traveltimes τpq computed according to Fermat\\'s interferometric principle. We denote this principle as the ‘traveltime holographic principle’, by analogy with the holographic principle in cosmology where information in a volume is encoded on the region\\'s boundary.
Cryogenic holographic distortion testing
Michel, David G.
1994-06-01
Hughes cryogenic holographic test facility allows for the rapid characterization of optical components and mechanical structures at elevated and reduced temperatures. The facility consists of a 1.6 meter diameter thermal vacuum chamber, vibration isolated experiment test platform, and a holographic camera assembly. Temperatures as low as 12 Kelvin and as high as 350 Kelvin have been demonstrated. Complex aspheric mirrors are tested without the need for auxiliary null lenses and may be tested in either the polished or unpolished state. Structural elements such as optical benches, solar array panels, and spacecraft antennas have been tested. Types of materials tested include beryllium, silicon carbide, aluminum, graphite epoxy, silicon/aluminum matrix material and injection molded plastics. Sizes have ranged from 7 cm X 15 cm to 825 cm X 1125 cm and have weighed as little as 0.2 Kg and as much as 130 Kg. Surface figure changes as little as (lambda) /10 peak-to-valley ((lambda) equals .514 micrometers ) are routinely measured.
Optoelectronic Oscillators for Communication Systems
Romeira, Bruno; Figueiredo, José
We introduce and report recent developments on a novel five port optoelectronic voltage controlled oscillator consisting of a resonant tunneling diode (RTD) optical-waveguide integrated with a laser diode. The RTD-based optoelectronic oscillator (OEO) has both optical and electrical input and output ports, with the fifth port allowing voltage control. The RTD-OEO locks to reference radio-frequency (RF) sources by either optical or electrical injection locking techniques allowing remote synchronization, eliminating the need of impedance matching between traditional RF oscillators. RTD-OEO functions include generation, amplification and distribution of RF carriers, clock recovery, carrier recovery, modulation and demodulation and frequency synthesis. Self-injection locking operation modes, where small portions of the output electrical/optical signals are fed back into the electrical/optical input ports, are also proposed. The self-phase locked loop configuration can give rise to low-noise high-stable oscillations, not limited by the RF source performance and with no need of external optoelectronic conversion.
Nanofabrication of Hybrid Optoelectronic Devices
Dibos, Alan Michael
The material requirements for optoelectronic devices can vary dramatically depending on the application. Often disparate material systems need to be combined to allow for full device functionality. At the nanometer scale, this can often be challenging because of the inherent chemical and structural incompatibilities of nanofabrication. This dissertation concerns the integration of seemingly dissimilar materials into hybrid optoelectronic devices for photovoltaic, plasmonic, and photonic applications. First, we show that combining a single strip of conjugated polymer and inorganic nanowire can yield a nanoscale solar cell, and modeling of optical absorption and exciton diffusion in this device can provide insight into the efficiency of charge separation. Second, we use an on-chip nanowire light emitting diode to pump a colloidal quantum dot coupled to a silver waveguide. The resulting device is an electro-optic single plasmon source. Finally, we transfer diamond waveguides onto near-field avalanche photodiodes fabricated from GaAs. Embedded in the diamond waveguides are nitrogen vacancy color centers, and the mapping of emission from these single-photon sources is demonstrated using our on-chip detectors, eliminating the need for external photodetectors on an optical table. These studies show the promise of hybrid optoelectronic devices at the nanoscale with applications in alternative energy, optical communication, and quantum optics.
Generalized Semi-Holographic Universe
Li, Hui; Zhang, Yi
2012-01-01
We study the semi-holographic idea in context of decaying dark components. The energy flow between dark energy and the compensating dark matter is thermodynamically generalized to involve a particle number variable dark component with non-zero chemical potential. It's found that, unlike the original semi-holographic model, no cosmological constant is needed for a dynamical evolution of the universe. A transient phantom phase appears while a non-trivial dark energy-dark matter scaling solution keeps at late time, which evades the big-rip and helps to resolve the coincidence problem. For reasonable parameters, the deceleration parameter is well consistent with current observations. The original semi-holographic model is extended and it also suggests that the concordance model may be reconstructed from the semi-holographic idea.
Adventures in Holographic Dimer Models
Energy Technology Data Exchange (ETDEWEB)
Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC; Karch, Andreas; /Washington U., Seattle; Yaida, Sho; /Stanford U., Phys. Dept.
2011-08-12
We abstract the essential features of holographic dimer models, and develop several new applications of these models. Firstly, semi-holographically coupling free band fermions to holographic dimers, we uncover novel phase transitions between conventional Fermi liquids and non-Fermi liquids, accompanied by a change in the structure of the Fermi surface. Secondly, we make dimer vibrations propagate through the whole crystal by way of double trace deformations, obtaining nontrivial band structure. In a simple toy model, the topology of the band structure experiences an interesting reorganization as we vary the strength of the double trace deformations. Finally, we develop tools that would allow one to build, in a bottom-up fashion, a holographic avatar of the Hubbard model.
Code properties from holographic geometries
Pastawski, Fernando
2016-01-01
Almheiri, Dong, and Harlow [hep-th/1411.7041] proposed a highly illuminating connection between the AdS/CFT holographic correspondence and operator algebra quantum error correction (OAQEC). Here we explore this connection further. We derive some general results about OAQEC, as well as results that apply specifically to quantum codes which admit a holographic interpretation. We introduce a new quantity called `price', which characterizes the support of a protected logical system, and find constraints on the price and the distance for logical subalgebras of quantum codes. We show that holographic codes defined on bulk manifolds with asymptotically negative curvature exhibit `uberholography', meaning that a bulk logical algebra can be supported on a boundary region with a fractal structure. We argue that, for holographic codes defined on bulk manifolds with asymptotically flat or positive curvature, the boundary physics must be highly nonlocal, an observation with potential implications for black holes and for q...
Hyperspectral holographic Fourier-microscopy
Energy Technology Data Exchange (ETDEWEB)
Kalenkov, G S [Moscow Institute of Physics and Technology (State University), Moscow (Russian Federation); Kalenkov, S G [Moscow State University of Mechanical Engineering, Moscow (Russian Federation); Shtan' ko, A E [Moscow State University of Technology ' Stankin' , Moscow (Russian Federation)
2015-04-30
A detailed theory of the method of holographic recording of hyperspectral wave fields is developed. New experimentally obtained hyperspectral holographic images of microscopic objects are presented. The possibilities of the method are demonstrated experimentally using the examples of urgent microscopy problems: speckle noise suppression, obtaining hyperspectral image of a microscopic object, as well as synthesis of a colour image and obtaining an optical profile of a phase object. (holography)
Segmented holographic spectrum splitting concentrator
Ayala, Silvana P.; Vorndran, Shelby; Wu, Yuechen; Chrysler, Benjamin; Kostuk, Raymond K.
2016-09-01
This paper presents a segmented parabolic concentrator employing holographic spectral filters that provide focusing and spectral bandwidth separation capability to the system. Strips of low band gap silicon photovoltaic (PV) cells are formed into a parabolic surface as shown by Holman et. al. [1]. The surface of the PV segments is covered with holographic elements formed in dichromated gelatin. The holographic elements are designed to transmit longer wavelengths to silicon cells, and to reflect short wavelength light towards a secondary collector where high-bandgap PV cells are mounted. The system can be optimized for different combinations of diffuse and direct solar illumination conditions for particular geographical locations by controlling the concentration ratio and filtering properties of the holographic elements. In addition, the reflectivity of the back contact of the silicon cells is used to increase the optical path length and light trapping. This potentially allows the use of thin film silicon for the low bandgap PV cell material. The optical design combines the focusing properties of the parabolic concentrator and the holographic element to control the concentration ratio and uniformity of the spectral distribution at the high bandgap cell location. The presentation concludes with a comparison of different spectrum splitting holographic filter materials for this application.
Progress of Si-based Optoelectronic Devices
Institute of Scientific and Technical Information of China (English)
PENG Ying-cai; FU Guang-sheng; WANG Ying-long; SHANG Yong
2004-01-01
Si-based optoelectronics is becoming a very active research area due to its potential applications to optical communications. One of the major goals of this study is to realize ali-Si optoelectronic integrated circuit. This is due to the fact that Si- based optoelectronic technology can be compatible with Si microelectronic technology. If Si-based optoelectronic devices and integrated circuits can be achieved,it will lead to a new informational technological revolution. In the article, the current developments of this exciting field are mainly reviewed in the recent years. The involved contents are the realization of various Si-based optoelectronic devices, such as light-emitting diodes,optical waveguides devices, Si photonic bandgap crystals,and Si laser,etc. Finally, the developed tendency of all-Si optoelectronic integrated technology are predicted in the near future.
Taylor, Marika
2016-01-01
The F theorem states that, for a unitary three dimensional quantum field theory, the F quantity defined in terms of the partition function on a three sphere is positive, stationary at fixed point and decreases monotonically along a renormalization group flow. We construct holographic renormalization group flows corresponding to relevant deformations of three-dimensional conformal field theories on spheres, working to quadratic order in the source. For these renormalization group flows, the F quantity at the IR fixed point is always less than F at the UV fixed point, but F increases along the RG flow for deformations by operators of dimension $3/2 < \\Delta < 5/2$. Therefore the strongest version of the F theorem is in general violated.
Losing Forward Momentum Holographically
Balasubramanian, Koushik
2013-01-01
We present a numerical scheme for solving Einstein's Equations in the presence of a negative cosmological constant and an event horizon with planar topology. Our scheme allows for the introduction of a particular metric source at the conformal boundary. Such a spacetime has a dual holographic description in terms of a strongly interacting quantum field theory at nonzero temperature. By introducing a sinusoidal static metric source that breaks translation invariance, we study momentum relaxation in the field theory. In the long wavelength limit, our results are consistent with the fluid-gravity correspondence and relativistic hydrodynamics. In the small amplitude limit, our results are consistent with the memory function prediction for the momentum relaxation rate. Our numerical scheme allows us to study momentum relaxation outside these two limits as well.
Brünner, Frederic; Rebhan, Anton
2014-01-01
We announce new results on glueball decay rates in the Sakai-Sugimoto model, a realization of holographic QCD from first principles that has only one coupling constant and an overall mass scale as free parameters. We extend a previous investigation by Hashimoto, Tan, and Terashima who have considered the lowest scalar glueball which arises from a somewhat exotic polarization of supergravity modes and whose mass is uncomfortably small in comparison with lattice results. On the other hand, the scalar glueball dual to the dilaton turns out to have a mass of about twice the mass of the rho meson (1487 MeV), very close to the scalar meson $f_0(1500)$ that is frequently interpreted as predominantly glue. Calculating the decay rate into two pions we find a surprisingly good agreement with experimental data for the $f_0(1500)$. We have also obtained decay widths for tensor and excited scalar glueballs, indicating universal narrowness.
Engineering holographic phase diagrams
Chen, Jiunn-Wei; Dai, Shou-Huang; Maity, Debaprasad; Zhang, Yun-Long
2016-10-01
By introducing interacting scalar fields, we tried to engineer physically motivated holographic phase diagrams which may be interesting in the context of various known condensed matter systems. We introduce an additional scalar field in the bulk which provides a tunable parameter in the boundary theory. By exploiting the way the tuning parameter changes the effective masses of the bulk interacting scalar fields, desired phase diagrams can be engineered for the boundary order parameters dual to those scalar fields. We give a few examples of generating phase diagrams with phase boundaries which are strikingly similar to the known quantum phases at low temperature such as the superconducting phases. However, the important difference is that all the phases we have discussed are characterized by neutral order parameters. At the end, we discuss if there exists any emerging scaling symmetry associated with a quantum critical point hidden under the dome in this phase diagram.
Holographic Special Relativity
Wise, Derek K
2013-01-01
We reinterpret special relativity, or more precisely its de Sitter deformation, in terms of 3d conformal geometry, as opposed to (3+1)d spacetime geometry. An inertial observer, usually described by a geodesic in spacetime, becomes instead a choice of ways to reverse the conformal compactification of a Euclidean vector space up to scale. The observer's "current time," usually given by a point along the geodesic, corresponds to the choice of scale in the decompactification. We also show how arbitrary conformal 3-geometries give rise to "observer space geometries," as defined in recent work, from which spacetime can be reconstructed under certain integrability conditions. We conjecture a relationship between this kind of "holographic relativity" and the "shape dynamics" proposal of Barbour and collaborators, in which conformal space takes the place of spacetime in general relativity. We also briefly survey related pictures of observer space, including the AdS analog and a representation related to twistor theor...
Comments on Holographic Complexity
Carmi, Dean; Rath, Pratik
2016-01-01
We study two recent conjectures for holographic complexity: the complexity=action conjecture and the complexity=volume conjecture. In particular, we examine the structure of the UV divergences appearing in these quantities, and show that the coefficients can be written as local integrals of geometric quantities in the boundary. We also consider extending these conjectures to evaluate the complexity of the mixed state produced by reducing the pure global state to a specific subregion of the boundary time slice. The UV divergences in this subregion complexity have a similar geometric structure, but there are also new divergences associated with the geometry of the surface enclosing the boundary region of interest. We discuss possible implications arising from the geometric nature of these UV divergences.
Covariant holographic entanglement negativity
Chaturvedi, Pankaj; Sengupta, Gautam
2016-01-01
We conjecture a holographic prescription for the covariant entanglement negativity of $d$-dimensional conformal field theories dual to non static bulk $AdS_{d+1}$ gravitational configurations in the framework of the $AdS/CFT$ correspondence. Application of our conjecture to a $AdS_3/CFT_2$ scenario involving bulk rotating BTZ black holes exactly reproduces the entanglement negativity of the corresponding $(1+1)$ dimensional conformal field theories and precisely captures the distillable quantum entanglement. Interestingly our conjecture for the scenario involving dual bulk extremal rotating BTZ black holes also accurately leads to the entanglement negativity for the chiral half of the corresponding $(1+1)$ dimensional conformal field theory at zero temperature.
Johnson, Clifford V
2014-01-01
It is shown that in theories of gravity where the cosmological constant is considered a thermodynamic variable, it is natural to use black holes as heat engines. Two examples are presented in detail using AdS charged black holes as the working substance. We notice that for static black holes, the maximally efficient traditional Carnot engine is also a Stirling engine. The case of negative cosmological constant supplies a natural realization of these engines in terms of the field theory description of the fluids to which they are holographically dual. We first propose a precise picture of how the traditional thermodynamic dictionary of holography is extended when the cosmological constant is dynamical and then conjecture that the engine cycles can be performed by using renormalization group flow. We speculate about the existence of a natural dual field theory counterpart to the gravitational thermodynamic volume.
Dissecting holographic conductivities
Davison, Richard A
2015-01-01
The DC thermoelectric conductivities of holographic systems in which translational symmetry is broken can be efficiently computed in terms of the near-horizon data of the dual black hole. By calculating the frequency dependent conductivities to the first subleading order in the momentum relaxation rate, we give a physical explanation for these conductivities in the simplest such example, in the limit of slow momentum relaxation. Specifically, we decompose each conductivity into the sum of a coherent contribution due to momentum relaxation and an incoherent contribution, due to intrinsic current relaxation. This decomposition is different from those previously proposed, and is consistent with the known hydrodynamic properties in the translationally invariant limit. This is the first step towards constructing a consistent theory of charged hydrodynamics with slow momentum relaxation.
Jokela, Niko; Järvinen, Matti; Lippert, Matthew
2017-04-01
Holographic models provide unique laboratories to investigate nonlinear physics of transport in inhomogeneous systems. We provide a detailed account of both dc and ac conductivities in a defect conformal field theory with spontaneous stripe order. The spatial symmetry is broken at large chemical potential, and the resulting ground state is a combination of a spin and charge density wave. An infinitesimal applied electric field across the stripes will cause the stripes to slide over the underlying density of smeared impurities, a phenomenon which can be associated with the Goldstone mode for the spontaneously broken translation symmetry. We show that the presence of a spatially modulated background magnetization current thwarts the expression of some dc conductivities in terms of horizon data.
Lasers and optoelectronics fundamentals, devices and applications
Maini, Anil K
2013-01-01
With emphasis on the physical and engineering principles, this book provides a comprehensive and highly accessible treatment of modern lasers and optoelectronics. Divided into four parts, it explains laser fundamentals, types of lasers, laser electronics & optoelectronics, and laser applications, covering each of the topics in their entirety, from basic fundamentals to advanced concepts. Key features include: exploration of technological and application-related aspects of lasers and optoelectronics, detailing both existing and emerging applications in industry, medical diag
Andersen, G.
For the last two decades adaptive optics has been used as a technique for correcting imaging applications and directed energy/laser targeting and laser communications systems affected by atmospheric turbulence. Typically these systems are bulky and limited to system with the potential to operate at speeds of MHz. The system utilizes a hologram to perform an all-optical wavefront analysis that removes the need for any computer. Finally, the sensing is made on a modal basis so it is largely insensitive to scintillation and obscuration. We have constructed a prototype device and will present experimental results from our research. The holographic adaptive optics system begins with the creation of a multiplexed hologram. This hologram is created by recording the maximum and minimum response functions of every actuator in the deformable mirror against a unique focused reference beam. When a wavefront of some arbitrary phase is incident on the processed hologram, a number of focal spots are created -- one pair for each actuator in the DM. The absolute phase error at each particular actuator location is simply related to the ratio of the intensity of each pair of spots. In this way we can use an array of photodetectors to give a direct readout of phase error without the need for any calculations. The advantages of holographic adaptive optics are many. To begin with, the measurement of phase error is made all optically, so the wavefront sensor directly controls the actuators in the DM without any computers. Using fast, photon counting photodetectors allows for closed loop correction limited only by the speed of the deformable mirror which in the case of MEMS devices can be 100 kHz or more. All this can be achieved in an extremely compact and lightweight package making it perfectly suited to applications such as UAV surveillance imagery and free space optical communications systems. Lastly, since the correction is made on a modal basis instead of zonal, it is virtually
3D holographic printer: fast printing approach.
Morozov, Alexander V; Putilin, Andrey N; Kopenkin, Sergey S; Borodin, Yuriy P; Druzhin, Vladislav V; Dubynin, Sergey E; Dubinin, German B
2014-02-10
This article describes the general operation principles of devices for synthesized holographic images such as holographic printers. Special emphasis is placed on the printing speed. In addition, various methods to increase the printing process are described and compared.
Holographic Waveguided See-Through Display Project
National Aeronautics and Space Administration — To address the NASA need for lightweight, space suit-mounted displays, Luminit proposes a novel Holographic Waveguided See-Through Display. Our proposed Holographic...
Small Molecule Organic Optoelectronic Devices
Bakken, Nathan
Organic optoelectronics include a class of devices synthesized from carbon containing 'small molecule' thin films without long range order crystalline or polymer structure. Novel properties such as low modulus and flexibility as well as excellent device performance such as photon emission approaching 100% internal quantum efficiency have accelerated research in this area substantially. While optoelectronic organic light emitting devices have already realized commercial application, challenges to obtain extended lifetime for the high energy visible spectrum and the ability to reproduce natural white light with a simple architecture have limited the value of this technology for some display and lighting applications. In this research, novel materials discovered from a systematic analysis of empirical device data are shown to produce high quality white light through combination of monomer and excimer emission from a single molecule: platinum(II) bis(methyl-imidazolyl)toluene chloride (Pt-17). Illumination quality achieved Commission Internationale de L'Eclairage (CIE) chromaticity coordinates (x = 0.31, y = 0.38) and color rendering index (CRI) > 75. Further optimization of a device containing Pt-17 resulted in a maximum forward viewing power efficiency of 37.8 lm/W on a plain glass substrate. In addition, accelerated aging tests suggest high energy blue emission from a halogen-free cyclometalated platinum complex could demonstrate degradation rates comparable to known stable emitters. Finally, a buckling based metrology is applied to characterize the mechanical properties of small molecule organic thin films towards understanding the deposition kinetics responsible for an elastic modulus that is both temperature and thickness dependent. These results could contribute to the viability of organic electronic technology in potentially flexible display and lighting applications. The results also provide insight to organic film growth kinetics responsible for optical
Optoelectronic tweezers for medical diagnostics
Kremer, Clemens; Neale, Steven; Menachery, Anoop; Barrett, Mike; Cooper, Jonathan M.
2012-01-01
Optoelectronic tweezers (OET) allows the spatial patterning of electric fields through selected illumination of a photoconductive surface. This enables the manipulation of micro particles and cells by creating non-uniform electrical fields that then produce dielectrophoretic (DEP) forces. The DEP responses of cells differ and can produce negative or positive (repelled or attracted to areas of high electric field) forces. Therefore OET can be used to manipulate individual cells and separate different cell types from each other. Thus OET has many applications for medical diagnostics, demonstrated here with work towards diagnosing Human African Trypanosomiasis, also known as sleeping sickness.
Digital holographic-based cancellable biometric for personal authentication
Verma, Gaurav; Sinha, Aloka
2016-05-01
In this paper, we propose a new digital holographic-based cancellable biometric scheme for personal authentication and verification. The realization of cancellable biometric is presented by using an optoelectronic experimental approach, in which an optically recorded hologram of the fingerprint of a person is numerically reconstructed. Each reconstructed feature has its own perspective, which is utilized to generate user-specific fingerprint features by using a feature-extraction process. New representations of the user-specific fingerprint features can be obtained from the same hologram, by changing the reconstruction distance (d) by an amount Δd between the recording plane and the reconstruction plane. This parameter is the key to make the cancellable user-specific fingerprint features using a digital holographic technique, which allows us to choose different reconstruction distances when reissuing the user-specific fingerprint features in the event of compromise. We have shown theoretically that each user-specific fingerprint feature has a unique identity with a high discrimination ability, and the chances of a match between them are minimal. In this aspect, a recognition system has also been demonstrated using the fingerprint biometric of the enrolled person at a particular reconstruction distance. For the performance evaluation of a fingerprint recognition system—the false acceptance ratio, the false rejection ratio and the equal error rate are calculated using correlation. The obtained results show good discrimination ability between the genuine and the impostor populations with the highest recognition rate of 98.23%.
Fourier holographic display for augmented reality using holographic optical element
Li, Gang; Lee, Dukho; Jeong, Youngmo; Lee, Byoungho
2016-03-01
A method for realizing a three-dimensional see-through augmented reality in Fourier holographic display is proposed. A holographic optical element (HOE) with the function of Fourier lens is adopted in the system. The Fourier hologram configuration causes the real scene located behind the lens to be distorted. In the proposed method, since the HOE is transparent and it functions as the lens just for Bragg matched condition, there is not any distortion when people observe the real scene through the lens HOE (LHOE). Furthermore, two optical characteristics of the recording material are measured for confirming the feasibility of using LHOE in the proposed see-through augmented reality holographic display. The results are verified experimentally.
Loop Quantum Gravity, Exact Holographic Mapping, and Holographic Entanglement Entropy
Han, Muxin
2016-01-01
The relation between Loop Quantum Gravity (LQG) and tensor network is explored from the perspectives of bulk-boundary duality and holographic entanglement entropy. We find that the LQG spin-network states in a space $\\Sigma$ with boundary $\\partial\\Sigma$ is an exact holographic mapping similar to the proposal in arXiv:1309.6282. The tensor network, understood as the boundary quantum state, is the output of the exact holographic mapping emerging from a coarse graining procedure of spin-networks. Furthermore, when a region $A$ and its complement $\\bar{A}$ are specified on the boundary $\\partial\\Sigma$, we show that the boundary entanglement entropy $S(A)$ of the emergent tensor network satisfies the Ryu-Takayanagi formula in the semiclassical regime, i.e. $S(A)$ is proportional to the minimal area of the bulk surface attached to the boundary of $A$ in $\\partial\\Sigma$.
Optoelectronic Applications of Colloidal Quantum Dots
Wang, Zhiping; Zhang, Nanzhu; Brenneman, Kimber; Wu, Tsai Chin; Jung, Hyeson; Biswas, Sushmita; Sen, Banani; Reinhardt, Kitt; Liao, Sicheng; Stroscio, Michael A.; Dutta, Mitra
This chapter highlights recent optoelectronic applications of colloidal quantum dots (QDs). In recent years, many colloidal QD-based optoelectronic devices, and device concepts have been proposed and studied. Many of these device concepts build on traditional optoelectronic device concepts. Increasingly, many new optoelectronic device concepts have been based on the use of biomolecule QD complexes. In this chapter, both types of structures are discussed. Special emphasis is placed on new optoelectronic device concepts that incorporate DNA-based aptamers in biomolecule QD complexes. Not only are the extensions of traditional devices and concepts realizable, such as QD-based photo detectors, displays, photoluminescent and photovoltaic devices, light-emitting diodes (LEDs), photovoltaic devices, and solar cells, but new devices concepts such a biomolecule-based molecular sensors possible. This chapter highlights a number of such novel QD-based devices and device concepts.
Organic optoelectronics:materials,devices and applications
Institute of Scientific and Technical Information of China (English)
LIU Yi; CUI Tian-hong
2005-01-01
The interest in organic materials for optoelectronic devices has been growing rapidly in the last two decades. This growth has been propelled by the exciting advances in organic thin films for displays, low-cost electronic circuits, etc. An increasing number of products employing organic electronic devices have become commercialized, which has stimulated the age of organic optoelectronics. This paper reviews the recent progress in organic optoelectronic technology. First, organic light emitting electroluminescent materials are introduced. Next, the three kinds of most important organic optoelectronic devices are summarized, including light emitting diode, organic photovoltaic cell, and photodetectors. The various applications of these devices are also reviewed and discussed in detail. Finally, the market and future development of optoelectronic devices are also demonstrated.
Wrapped optoelectronic devices and methods for making same
Energy Technology Data Exchange (ETDEWEB)
Curran, Seamus; Dias, Sampath; Alley, Nigel; Haldar, Amrita; Yambem, Soniya Devi; Kang-Shyang, Liao; Chaudhari, Prajakta
2017-07-11
In various embodiments, optoelectronic devices are described herein. The optoelectronic device may include an optoelectronic cell arranged so as to wrap around a central axis wherein the cell includes a first conductive layer, a semi-conductive layer disposed over and in electrical communication with the first conductive layer, and a second conductive layer disposed over and in electrical communication with the semi-conductive layer. In various embodiments, methods for making optoelectronic devices are described herein. The methods may include forming an optoelectronic cell while flat and wrapping the optoelectronic cell around a central axis. The optoelectronic devices may be photovoltaic devices. Alternatively, the optoelectronic devices may be organic light emitting diodes.
Holographic Duality in Condensed Matter Physics
Zaanen, Jan; Liu, Yan; Sun, Ya-Wen; Schalm, Koenraad
2015-11-01
Preface; 1. Introduction; 2. Condensed matter: the charted territory; 3. Condensed matter: the challenges; 4. Large N field theories for holography and condensed matter; 5. The AdS/CFT correspondence as computational device: the dictionary; 6. Finite temperature magic: black holes and holographic thermodynamics; 7. Holographic hydrodynamics; 8. Finite density: the Reissner-Nordström black hole and strange metals; 9. Holographic photoemission and the RN metal: the fermions as probes; 10. Holographic superconductivity; 11. Holographic Fermi liquids; 12. Breaking translational invariance; 13. AdS/CMT from the top down; 14. Outlook: holography and quantum matter; References; Index.
Full Color Holographic Endoscopy
Osanlou, A.; Bjelkhagen, H.; Mirlis, E.; Crosby, P.; Shore, A.; Henderson, P.; Napier, P.
2013-02-01
The ability to produce color holograms from the human tissue represents a major medical advance, specifically in the areas of diagnosis and teaching. This has been achieved at Glyndwr University. In corporation with partners at Gooch & Housego, Moor Instruments, Vivid Components and peninsula medical school, Exeter, UK, for the first time, we have produced full color holograms of human cell samples in which the cell boundary and the nuclei inside the cells could be clearly focused at different depths - something impossible with a two-dimensional photographic image. This was the main objective set by the peninsula medical school at Exeter, UK. Achieving this objective means that clinically useful images essentially indistinguishable from the object human cells could be routinely recorded. This could potentially be done at the tip of a holo-endoscopic probe inside the body. Optimised recording exposure and development processes for the holograms were defined for bulk exposures. This included the optimisation of in-house recording emulsions for coating evaluation onto polymer substrates (rather than glass plates), a key step for large volume commercial exploitation. At Glyndwr University, we also developed a new version of our in-house holographic (world-leading resolution) emulsion.
Holographic films from carotenoid pigments
Toxqui-López, S.; Lecona-Sánchez, J. F.; Santacruz-Vázquez, C.; Olivares-Pérez, A.; Fuentes-Tapia, I.
2014-02-01
Carotenoids pigments presents in pineapple can be more than just natural dyes, which is one of the applications that now at day gives the chemical industry. In this research shown that can be used in implementing of holographic recording Films. Therefore we describe the technique how to obtain this kind of pigments trough spay drying of natural pineapple juice, which are then dissolved with water in a proportion of 0.1g to 1mL. The obtained sample is poured into glass substrates using the gravity method, after a drying of 24 hours in laboratory normal conditions the films are ready. The films are characterized by recording transmission holographic gratings (LSR 445 NL 445 nm) and measuring the diffraction efficiency holographic parameter. This recording material has good diffraction efficiency and environmental stability.
Holographic Pomeron: Saturation and DIS
Stoffers, Alexander
2012-01-01
We briefly review the approach to dipole-dipole scattering in holographic QCD developed in ARXIV:1202.0831. The Pomeron is modeled by exchanging closed strings between the dipoles and yields Regge behavior for the elastic amplitude. We calculate curvature corrections to this amplitude in both a conformal and confining background, identifying the holographic direction with the virtuality of the dipoles. The it wee-dipole density is related to the string tachyon diffusion in both virtuality and the transverse directions. We give an explicit derivation of the dipole saturation momentum both in the conformal and confining metric. Our holographic result for the dipole-dipole cross section and the it wee-dipole density in the conformal limit are shown to be identical in form to the BFKL pomeron result when the non-critical string transverse dimension is $D_\\perp=3$. The total dipole-dipole cross section is compared to DIS data from HERA.
Gauge invariance and holographic renormalization
Directory of Open Access Journals (Sweden)
Keun-Young Kim
2015-10-01
Full Text Available We study the gauge invariance of physical observables in holographic theories under the local diffeomorphism. We find that gauge invariance is intimately related to the holographic renormalization: the local counter terms defined in the boundary cancel most of gauge dependences of the on-shell action as well as the divergences. There is a mismatch in the degrees of freedom between the bulk theory and the boundary one. We resolve this problem by noticing that there is a residual gauge symmetry (RGS. By extending the RGS such that it satisfies infalling boundary condition at the horizon, we can understand the problem in the context of general holographic embedding of a global symmetry at the boundary into the local gauge symmetry in the bulk.
Toward a Holographic Theory for General Spacetimes
Nomura, Yasunori; Sanches, Fabio; Weinberg, Sean J
2016-01-01
We study a holographic theory of general spacetimes that does not rely on the existence of asymptotic regions. This theory is to be formulated in a holographic space. When a semiclassical description is applicable, the holographic space is assumed to be a holographic screen: a codimension-1 surface that is capable of encoding states of the gravitational spacetime. Our analysis is guided by conjectured relationships between gravitational spacetime and quantum entanglement in the holographic description. To understand basic features of this picture, we catalog predictions for the holographic entanglement structure of cosmological spacetimes. We find that qualitative features of holographic entanglement entropies for such spacetimes differ from those in AdS/CFT but that the former reduce to the latter in the appropriate limit. The Hilbert space of the theory is analyzed, and two plausible structures are found: a direct sum and "spacetime equals entanglement" structure. The former preserves a naive relationship b...
Fishman, Gadi; DeRowe, Ari; Ophir, Eyal; Scharf, Vered; Shabtai, Abraham; Ophir, Dov; Katzir, Abraham
1999-06-01
Clinical diagnosis of acute otitis media (AOM) in children is not easy. It was assumed that there is a difference ΔT between the Tympanic Membrane (TM) temperatures in the two ears in unilateral AOM and that an accurate measurement of ΔT may improve the diagnosis accuracy. An IR transmitting fiber, made of AgClBr, was coupled into a hand held otoscope and was used for the non-contact (radiometric) measurements of TT, the TM temperature. Experiments were carried out, first, on a laboratory model that simulated the human ear, including an artificial tympanic membrane and an artificial ear canal. Measurements carried out using commercially available tympanic thermometers shown that the temperature Tc of the ear canal affected the results. Tc did not affect the fiberoptic radiometer, and this device accurately measured the true temperature, TT of the tympanic membrane. A prospective blinded sampling of the TM temperature was then performed on 48 children with suspected AOM. The mean temperature difference between the ears, for children with unilateral AOM was ΔT = (0.68 +/- 0.27)°C. For children with bilateral AOM it was ΔT = (0.14+/-0.10)°C (p<0.001). It was demonstrated that afor unilateral AOM the difference ΔT was proportional to the systemic temperature. In conclusion, the fiberoptic interferometric measurements of the TM can be a useful non-invasive diagnostic tool for AOM, when combined with other data.
Transparent Electrodes for Efficient Optoelectronics
Morales-Masis, Monica
2017-03-30
With the development of new generations of optoelectronic devices that combine high performance and novel functionalities (e.g., flexibility/bendability, adaptability, semi or full transparency), several classes of transparent electrodes have been developed in recent years. These range from optimized transparent conductive oxides (TCOs), which are historically the most commonly used transparent electrodes, to new electrodes made from nano- and 2D materials (e.g., metal nanowire networks and graphene), and to hybrid electrodes that integrate TCOs or dielectrics with nanowires, metal grids, or ultrathin metal films. Here, the most relevant transparent electrodes developed to date are introduced, their fundamental properties are described, and their materials are classified according to specific application requirements in high efficiency solar cells and flexible organic light-emitting diodes (OLEDs). This information serves as a guideline for selecting and developing appropriate transparent electrodes according to intended application requirements and functionality.
Optoelectronics of Molecules and Polymers
Moliton, André
2006-01-01
Optoelectronic devices are being developed at an extraordinary rate. Organic light emitting diodes, photovoltaic devices and electro-optical modulators are pivotal to the future of displays, photosensors and solar cells, and communication technologies. This book details the theories underlying the relevant mechanisms in organic materials and covers, at a basic level, how the organic components are made. The first part of this book introduces the fundamental theories used to detail ordered solids and localised energy levels. The methods used to determine energy levels in perfectly ordered molecular and macromolecular systems are discussed, making sure that the effects of quasi-particles are not missed. The function of excitons and their transfer between two molecules are studied, and the problems associated with interfaces and charge injection into resistive media are presented. The second part details technological aspects such as the fabrication of devices based on organic materials by dry etching. The princ...
Holographic Multi-Band Superconductor
Huang, Ching-Yu; Maity, Debaprasad
2011-01-01
We propose a gravity dual for the holographic superconductor with multi-band carriers. Moreover, the currents of these carriers are unified under a global non-Abelian symmetry, which is dual to the bulk non-Abelian gauge symmetry. We study the phase diagram of our model, and find it qualitatively agrees with the one for the realistic 2-band superconductor, such as MgB2. We also evaluate the holographic conductivities and find the expected mean-field like behaviors in some cases. However, for a wide range of the parameter space, we also find the non-mean-field like behavior with negative conductivities.
DHMI: dynamic holographic microscopy interface
He, Xuefei; Zheng, Yujie; Lee, Woei Ming
2016-12-01
Digital holographic microscopy (DHM) is a powerful in-vitro biological imaging tool. In this paper, we report a fully automated off-axis digital holographic microscopy system completed with a graphical user interface in the Matlab environment. The interface primarily includes Fourier domain processing, phase reconstruction, aberration compensation and autofocusing. A variety of imaging operations such as region of interest selection, de-noising mode (filtering and averaging), low frame rate imaging for immediate reconstruction and high frame rate imaging routine ( 27 fps) are implemented to facilitate ease of use.
Holographic Conductivity in Disordered Systems
Ryu, Shinsei; Ugajin, Tomonori
2011-01-01
The main purpose of this paper is to holographically study the behavior of conductivity in 2+1 dimensional disordered systems. We analyze probe D-brane systems in AdS/CFT with random closed string and open string background fields. We give a prescription of calculating the DC conductivity holographically in disordered systems. In particular, we find an analytical formula of the conductivity in the presence of codimension one randomness. We also systematically study the AC conductivity in various probe brane setups without disorder and find analogues of Mott insulators.
Holographic superconductors without translational symmetry
Zeng, Hua Bi
2014-01-01
A holographic superconductor is constructed in the background of a massive gravity theory. In the normal state without condensation, the conductivity exhibits a Drude peak that approaches a delta function in the massless gravity limit as studied by David Vegh. In the superconducting state, besides the infinite DC conductivity, the AC conductivity has Drude behavior at low frequency followed by a power law-fall. These results are in agreement with that found earlier by Horowitz and Santos, who studied a holographic superconductor with an implicit periodic potential beyond the probe limit. The results also agree with measurements on some cuprates.
Holographic microscopy in low coherence
Chmelík, Radim; Petráček, Jiří; Slabá, Michala; Kollárová, Věra; Slabý, Tomáš; Čolláková, Jana; Komrska, Jiří; Dostál, Zbyněk.; Veselý, Pavel
2016-03-01
Low coherence of the illumination substantially improves the quality of holographic and quantitative phase imaging (QPI) by elimination of the coherence noise and various artefacts and by improving the lateral resolution compared to the coherent holographic microscopy. Attributes of coherence-controlled holographic microscope (CCHM) designed and built as an off-axis holographic system allowing QPI within the range from complete coherent to incoherent illumination confirmed these expected advantages. Low coherence illumination also furnishes the coherence gating which constraints imaging of some spatial frequencies of an object axially thus forming an optical section in the wide sense. In this way the depth discrimination capability of the microscope is introduced at the price of restricting the axial interval of possible numerical refocusing. We describe theoretically these effects for the whole range of illumination coherence. We also show that the axial refocusing constraints can be overcome using advanced mode of imaging based on mutual lateral shift of reference and object image fields in CCHM. Lowering the spatial coherence of illumination means increasing its numerical aperture. We study how this change of the illumination geometry influences 3D objects QPI and especially the interpretation of live cells QPI in terms of the dry mass density measurement. In this way a strong dependence of the imaging process on the light coherence is demonstrated. The theoretical calculations and numerical simulations are supported by experimental data including a chance of time-lapse watching of live cells even in optically turbid milieu.
Lecture Notes on Holographic Renormalization
Skenderis, K
2002-01-01
We review the formalism of holographic renormalization. We start by discussing mathematical results on asymptotically anti-de Sitter spacetimes. We then outline the general method of holographic renormalization. The method is illustrated by working all details in a simple example: a massive scalar field on anti-de Sitter spacetime. The discussion includes the derivation of the on-shell renormalized action, of holographic Ward identities, anomalies and RG equations, and the computation of renormalized one-, two- and four-point functions. We then discuss the application of the method to holographic RG flows. We also show that the results of the near-boundary analysis of asymptotically AdS spacetimes can be analytically continued to apply to asymptotically de Sitter spacetimes. In particular, it is shown that the Brown-York stress energy tensor of de Sitter spacetime is equal, up to a dimension dependent sign, to the Brown-York stress energy tensor of an associated AdS spacetime.
Holographic complexity and spacetime singularities
Energy Technology Data Exchange (ETDEWEB)
Barbón, José L.F. [Instituto de Física Teórica IFT UAM/CSIC,C/ Nicolás Cabrera 13, Campus Universidad Autónoma de Madrid,Madrid 28049 (Spain); Rabinovici, Eliezer [Racah Institute of Physics, The Hebrew University,Jerusalem 91904 (Israel); Laboratoire de Physique Théorique et Hautes Energies, Université Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris Cedex 05 (France)
2016-01-15
We study the evolution of holographic complexity in various AdS/CFT models containing cosmological crunch singularities. We find that a notion of complexity measured by extremal bulk volumes tends to decrease as the singularity is approached in CFT time, suggesting that the corresponding quantum states have simpler entanglement structure at the singularity.
Picosecond Holographic-Grating Spectroscopy
Duppen, K.
1987-01-01
Interfering light waves produce an optical interference pattern in any medium that interacts with light. This modulation of some physical parameter of the system acts as a classical holographic grating for optical radiation. When such a grating is produced through interaction of pulsed light waves w
Holographic dark-energy models
Del Campo, Sergio; Fabris, Júlio. C.; Herrera, Ramón; Zimdahl, Winfried
2011-06-01
Different holographic dark-energy models are studied from a unifying point of view. We compare models for which the Hubble scale, the future event horizon or a quantity proportional to the Ricci scale are taken as the infrared cutoff length. We demonstrate that the mere definition of the holographic dark-energy density generally implies an interaction with the dark-matter component. We discuss the relation between the equation-of-state parameter and the energy density ratio of both components for each of the choices, as well as the possibility of noninteracting and scaling solutions. Parameter estimations for all three cutoff options are performed with the help of a Bayesian statistical analysis, using data from supernovae type Ia and the history of the Hubble parameter. The ΛCDM model is the clear winner of the analysis. According to the Bayesian information criterion (BIC), all holographic models should be considered as ruled out, since the difference ΔBIC to the corresponding ΛCDM value is >10. According to the Akaike information criterion (AIC), however, we find ΔAIC<2 for models with Hubble-scale and Ricci-scale cutoffs, indicating, that they may still be competitive. As we show for the example of the Ricci-scale case, also the use of certain priors, reducing the number of free parameters to that of the ΛCDM model, may result in a competitive holographic model.
Range Compressed Holographic Aperture Ladar
2017-06-01
digital holography, laser, active imaging, remote sensing, laser imaging 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT: SAR 8...slow speed tunable lasers, while relaxing the need to precisely track the transceiver or target motion. In the following section we describe a scenario...contrast targets. As shown in Figure 28, augmenting holographic ladar with range compression relaxes the dependence of image reconstruction on
Code Properties from Holographic Geometries
Pastawski, Fernando; Preskill, John
2017-04-01
Almheiri, Dong, and Harlow [J. High Energy Phys. 04 (2015) 163., 10.1007/JHEP04(2015)163] proposed a highly illuminating connection between the AdS /CFT holographic correspondence and operator algebra quantum error correction (OAQEC). Here, we explore this connection further. We derive some general results about OAQEC, as well as results that apply specifically to quantum codes that admit a holographic interpretation. We introduce a new quantity called price, which characterizes the support of a protected logical system, and find constraints on the price and the distance for logical subalgebras of quantum codes. We show that holographic codes defined on bulk manifolds with asymptotically negative curvature exhibit uberholography, meaning that a bulk logical algebra can be supported on a boundary region with a fractal structure. We argue that, for holographic codes defined on bulk manifolds with asymptotically flat or positive curvature, the boundary physics must be highly nonlocal, an observation with potential implications for black holes and for quantum gravity in AdS space at distance scales that are small compared to the AdS curvature radius.
Code Properties from Holographic Geometries
Directory of Open Access Journals (Sweden)
Fernando Pastawski
2017-05-01
Full Text Available Almheiri, Dong, and Harlow [J. High Energy Phys. 04 (2015 163.JHEPFG1029-847910.1007/JHEP04(2015163] proposed a highly illuminating connection between the AdS/CFT holographic correspondence and operator algebra quantum error correction (OAQEC. Here, we explore this connection further. We derive some general results about OAQEC, as well as results that apply specifically to quantum codes that admit a holographic interpretation. We introduce a new quantity called price, which characterizes the support of a protected logical system, and find constraints on the price and the distance for logical subalgebras of quantum codes. We show that holographic codes defined on bulk manifolds with asymptotically negative curvature exhibit uberholography, meaning that a bulk logical algebra can be supported on a boundary region with a fractal structure. We argue that, for holographic codes defined on bulk manifolds with asymptotically flat or positive curvature, the boundary physics must be highly nonlocal, an observation with potential implications for black holes and for quantum gravity in AdS space at distance scales that are small compared to the AdS curvature radius.
Unbalanced holographic superconductors and spintronics
Bigazzi, F.; Cotrone, A.L.; Musso, D.; Pinzani Fokeeva, N.; Seminara, D.
2012-01-01
We present a minimal holographic model for s-wave superconductivity with unbalanced Fermi mixtures, in 2 + 1 dimensions at strong coupling. The breaking of a U(1)A “charge” symmetry is driven by a non-trivial profile for a charged scalar field in a charged asymptotically AdS4 black hole. The chemica
Progress on the optoelectronic functional organic crystals
Institute of Scientific and Technical Information of China (English)
2007-01-01
Organic crystals constructed by pi-conjugated molecules have been paid great attention to in the field of organic optoelectronic materials. The superiorities of these organic crystal materials, such as high thermal stability, highly ordered structure, and high carrier mobility over the amorphous thin film ma-terials, make them attractive candidates for optoelectronic devices. Single crystal with definite struc-ture provides a model to investigate the basic interactions between the molecules (supramolecular interaction), and the relationship between molecular stacking modes and optoelectronic performance (luminescence and carrier mobility). Through modulating molecular arrangement in organic crystal, the luminescence efficiency of organic crystal has exceeded 80% and carrier mobility has been up to the level of 10 cm2·V?1·s?1. Amplified stimulated emission phenomena have been observed in many crys-tals. In this paper, we will emphatically introduce the progress in optoelectronic functional organic crystals and some correlative principle.
Opto-Electronic Oscillator and its Applications
Yao, X. S.; Maleki, L.
1996-01-01
We present the theoretical and experimental results of a new class of microwave oscillators called opto-electronic oscillators (OEO). We discuss techniques of achieving high stability single mode operation and demonstrate the applications of OEO in photonic communication systems.
Progress on the optoelectronic functional organic crystals
Institute of Scientific and Technical Information of China (English)
WANG Huan; XIE ZengQi; Ma YuGuang; Shen JiaCong
2007-01-01
Organic crystals constructed by pi-conjugated molecules have been paid great attention to in the field of organic optoelectronic materials. The superiorities of these organic crystal materials, such as high thermal stability, highly ordered structure, and high carrier mobility over the amorphous thin film materials, make them attractive candidates for optoelectronic devices. Single crystal with definite structure provides a model to investigate the basic interactions between the molecules (supramolecular interaction), and the relationship between molecular stacking modes and optoelectronic performance (luminescence and carrier mobility). Through modulating molecular arrangement in organic crystal, the luminescence efficiency of organic crystal has exceeded 80% and carrier mobility has been up to the level of 10 cm2·V-1·s-1. Amplified stimulated emission phenomena have been observed in many crystals. In this paper, we will emphatically introduce the progress in optoelectronic functional organic crystals and some correlative principle.
Radiation effects in optoelectronic devices. [Review
Energy Technology Data Exchange (ETDEWEB)
Barnes, C.E.; Wiczer, J.J.
1984-05-01
Purpose of this report is to provide not only a summary of radiation damage studies at Sandia National Laboratories, but also of those in the literature on the components of optoelectronic systems: light emitting diodes (LEDs), laser diodes, photodetectors, optical fibers, and optical isolators. This review of radiation damage in optoelectronic components is structured according to device type. In each section, a brief discussion of those device properties relevant to radiation effects is given.
Metal oxides for optoelectronic applications.
Yu, Xinge; Marks, Tobin J; Facchetti, Antonio
2016-04-01
Metal oxides (MOs) are the most abundant materials in the Earth's crust and are ingredients in traditional ceramics. MO semiconductors are strikingly different from conventional inorganic semiconductors such as silicon and III-V compounds with respect to materials design concepts, electronic structure, charge transport mechanisms, defect states, thin-film processing and optoelectronic properties, thereby enabling both conventional and completely new functions. Recently, remarkable advances in MO semiconductors for electronics have been achieved, including the discovery and characterization of new transparent conducting oxides, realization of p-type along with traditional n-type MO semiconductors for transistors, p-n junctions and complementary circuits, formulations for printing MO electronics and, most importantly, commercialization of amorphous oxide semiconductors for flat panel displays. This Review surveys the uniqueness and universality of MOs versus other unconventional electronic materials in terms of materials chemistry and physics, electronic characteristics, thin-film fabrication strategies and selected applications in thin-film transistors, solar cells, diodes and memories.
Metal oxides for optoelectronic applications
Yu, Xinge; Marks, Tobin J.; Facchetti, Antonio
2016-04-01
Metal oxides (MOs) are the most abundant materials in the Earth's crust and are ingredients in traditional ceramics. MO semiconductors are strikingly different from conventional inorganic semiconductors such as silicon and III-V compounds with respect to materials design concepts, electronic structure, charge transport mechanisms, defect states, thin-film processing and optoelectronic properties, thereby enabling both conventional and completely new functions. Recently, remarkable advances in MO semiconductors for electronics have been achieved, including the discovery and characterization of new transparent conducting oxides, realization of p-type along with traditional n-type MO semiconductors for transistors, p-n junctions and complementary circuits, formulations for printing MO electronics and, most importantly, commercialization of amorphous oxide semiconductors for flat panel displays. This Review surveys the uniqueness and universality of MOs versus other unconventional electronic materials in terms of materials chemistry and physics, electronic characteristics, thin-film fabrication strategies and selected applications in thin-film transistors, solar cells, diodes and memories.
Metamaterial mirrors in optoelectronic devices
Esfandyarpour, Majid
2014-06-22
The phase reversal that occurs when light is reflected from a metallic mirror produces a standing wave with reduced intensity near the reflective surface. This effect is highly undesirable in optoelectronic devices that use metal films as both electrical contacts and optical mirrors, because it dictates a minimum spacing between the metal and the underlying active semiconductor layers, therefore posing a fundamental limit to the overall thickness of the device. Here, we show that this challenge can be circumvented by using a metamaterial mirror whose reflection phase is tunable from that of a perfect electric mirror († = €) to that of a perfect magnetic mirror († = 0). This tunability in reflection phase can also be exploited to optimize the standing wave profile in planar devices to maximize light-matter interaction. Specifically, we show that light absorption and photocurrent generation in a sub-100 nm active semiconductor layer of a model solar cell can be enhanced by ∼20% over a broad spectral band. © 2014 Macmillan Publishers Limited.
Holographic kinetic k-essence model
Energy Technology Data Exchange (ETDEWEB)
Cruz, Norman [Departamento de Fisica, Facultad de Ciencia, Universidad de Santiago de Chile, Casilla 307, Santiago (Chile)], E-mail: ncruz@lauca.usach.cl; Gonzalez-Diaz, Pedro F.; Rozas-Fernandez, Alberto [Colina de los Chopos, Instituto de Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)], E-mail: a.rozas@cfmac.csic.es; Sanchez, Guillermo [Departamento de Matematica y Ciencia de la Computacion, Facultad de Ciencia, Universidad de Santiago de Chile, Casilla 307, Santiago (Chile)], E-mail: gsanchez@usach.cl
2009-08-31
We consider a connection between the holographic dark energy density and the kinetic k-essence energy density in a flat FRW universe. With the choice c{>=}1, the holographic dark energy can be described by a kinetic k-essence scalar field in a certain way. In this Letter we show this kinetic k-essential description of the holographic dark energy with c{>=}1 and reconstruct the kinetic k-essence function F(X)
Holographic complexity in gauge/string superconductors
Directory of Open Access Journals (Sweden)
Davood Momeni
2016-05-01
Full Text Available Following a methodology similar to [1], we derive a holographic complexity for two dimensional holographic superconductors (gauge/string superconductors with backreactions. Applying a perturbation method proposed by Kanno in Ref. [2], we study behaviors of the complexity for a dual quantum system near critical points. We show that when a system moves from the normal phase (T>Tc to the superconductor phase (T
Holographic entanglement entropy in imbalanced superconductors
Dutta, Arghya
2014-01-01
We study the behavior of holographic entanglement entropy (HEE) for imbalanced holographic superconductor. It is found that HEE for this imbalanced system decreases with the increase of imbalance in chemical potentials. Also for an arbitrary mismatch between two chemical potentials, below the critical temperature, superconducting phase has a lower HEE in comparison to the AdS-Reissner-Nordstrom black hole phase. This suggests entanglement entropy to be a useful physical probe for understanding the imbalanced holographic superconductors.
Holographic entanglement entropy in general holographic superconductor models
Peng, Yan
2014-01-01
We study the entanglement entropy of general holographic dual models both in AdS soliton and AdS black hole backgrounds with full backreaction. We find that the entanglement entropy is a good probe to explore the properties of the holographic superconductors and provides richer physics in the phase transition. We obtain the effects of the scalar mass, model parameter and backreaction on the entropy, and argue that the jump of the entanglement entropy may be a quite general feature for the first order phase transition. In strong contrast to the insulator/superconductor system, we note that the backreaction coupled with the scalar mass can not be used to trigger the first order phase transition if the model parameter is below its bottom bound in the metal/superconductor system.
Holographic QCD: Past, Present, and Future
Kim, Youngman; Tsukioka, Takuya
2012-01-01
At the dawn of a new theoretical tool based on AdS/CFT for non-perturbative aspects of quantum chromodynamics, we give an interim review on the the new tool, holographic QCD, with some of its accomplishment. We try to give an A-to-Z picture of the holographic QCD, from string theory to a few selected top-down holographic QCD models with one or two physical applications in each model. We may not attempt to collect diverse results from various holographic QCD model studies.
Holographic Two-Photon Induced Photopolymerization
Federal Laboratory Consortium — Holographic two-photon-induced photopolymerization (HTPIP) offers distinct advantages over conventional one-photon-induced photopolymerization and current techniques...
Understanding strongly coupling magnetism from holographic duality
Cai, Rong-Gen
2016-01-01
The unusual magnetic materials are significant in both science and technology. However, because of the strongly correlated effects, it is difficult to understand their novel properties from theoretical aspects. Holographic duality offers a new approach to understanding such systems from gravity side. This paper will give a brief review of our recent works on the applications of holographic duality in understanding unusual magnetic materials. Some quantitative compare between holographic results and experimental data will be shown and some predictions from holographic duality models will be discussed.
Optoelectronic microdevices for combined phototherapy
Zharov, Vladimir P.; Menyaev, Yulian A.; Hamaev, V. A.; Antropov, G. M.; Waner, Milton
2000-03-01
In photomedicine in some of cases radiation delivery to local zones through optical fibers can be changed for the direct placing of tiny optical sources like semiconductor microlasers or light diodes in required zones of ears, nostrils, larynx, nasopharynx cochlea or alimentary tract. Our study accentuates the creation of optoelectronic microdevices for local phototherapy and functional imaging by using reflected light. Phototherapeutic micromodule consist of the light source, microprocessor and miniature optics with different kind of power supply: from autonomous with built-in batteries to remote supply by using pulsed magnetic field and supersmall coils. The developed prototype photomodule has size (phi) 8X16 mm and work duration with built-in battery and light diode up several hours at the average power from several tenths of mW to few mW. Preliminary clinical tests developed physiotherapeutic micrimodules in stomatology for treating the inflammation and in otolaryngology for treating tonsillitis and otitis are presented. The developed implanted electro- optical sources with typical size (phi) 4X0,8 mm and with remote supply were used for optical stimulation of photosensitive retina structure and electrostimulation of visual nerve. In this scheme the superminiature coil with 30 electrical integrated levels was used. Such devices were implanted in eyes of 175 patients with different vision problems during clinical trials in Institute of Eye's Surgery in Moscow. For functional imaging of skin layered structure LED arrays coupled photodiodes arrays were developed. The possibilities of this device for study drug diffusion and visualization small veins are discussed.
Stealths on Anisotropic Holographic Backgrounds
Ayón-Beato, Eloy; Juárez-Aubry, María Montserrat
2015-01-01
In this paper, we are interested in exploring the existence of stealth configurations on anisotropic backgrounds playing a prominent role in the non-relativistic version of the gauge/gravity correspondence. By stealth configuration, we mean a nontrivial scalar field nonminimally coupled to gravity whose energy-momentum tensor evaluated on the anisotropic background vanishes identically. In the case of a Lifshitz spacetime with a nontrivial dynamical exponent z, we spotlight the role played by the anisotropy to establish the holographic character of the stealth configurations, i.e. the scalar field is shown to only depend on the radial holographic direction. This configuration which turns out to be massless and without integration constants is possible for a unique value of the nonminimal coupling parameter. Then, using a simple conformal argument, we map this configuration into a stealth solution defined on the so-called hyperscaling violation metric which is conformally related to the Lifshitz spacetime. Thi...
Holographic Fabry-Perot spectrometer.
Martínez-Matos, O; Rodrigo, José A; Vaveliuk, P; Calvo, M L
2011-02-15
We propose a spectrum analyzer based on the properties of a hologram recorded with the field transmitted by a Fabry-Perot etalon. The spectral response of this holographic Fabry-Perot spectrometer (HFPS) is analytically investigated in the paraxial approximation and compared with a conventional Fabry-Perot etalon of similar characteristics. We demonstrate that the resolving power is twice increased and the free spectral range (FSR) is reduced to one-half. The proposed spectrometer could improve the operational performance of the etalon because it can exhibit high efficiency and it would be insensible to environmental conditions such as temperature and vibrations. Our analysis also extends to another variant of the HFPS based on holographic multiplexing of the transmitted field of a Fabry-Perot etalon. This device increases the FSR, keeping the same HFPS performance.
Holographic Quenches with a Gap
da Silva, Emilia; Mas, Javier; Serantes, Alexandre
2016-01-01
In order to holographically model quenches with a gapped final hamiltonian, we consider a gravity-scalar theory in anti-de Sitter space with an infrared hard wall. We allow a time dependent profile for the scalar field at the wall. This induces an energy exchange between bulk and wall and generates an oscillating scalar pulse. We argue that such backgrounds are the counterpart of quantum revivals in the dual field theory. We perform a qualitative comparison with the quench dynamics of the massive Schwinger model, which has been recently analyzed using tensor network techniques. Agreement is found provided the width of the oscillating scalar pulse is inversely linked to the energy density communicated by the quench. We propose this to be a general feature of holographic quenches.
Holographic Mott-like insulator
Ling, Yi; Wu, Jian-Pin
2015-01-01
In this paper we show that a gravity dual model with Q-lattice structure can provide a holographic description of a Mott-like insulator, which is an extension of our previous work in arXiv:1507.02514. We construct the bulk geometry with two gauge fields and introduce a coupling between the lattice and the Maxwell field. It turns out that an insulating ground state with hard gap as well as vanishing DC conductivity can be achieved in the zero temperature limit, which can be viewed as a substantial progress towards the holographic construction of Mott-like insulator. The non-Drude behavior in optical conductivity is also discussed.
Holographic Chern-Simons Defects
Fujita, Mitsutoshi; Meyer, Rene; Sugimoto, Shigeki
2016-01-01
We study SU(N) Yang-Mills-Chern-Simons theory in the presence of defects that shift the Chern-Simons level from a holographic point of view by embedding the system in string theory. The model is a D3-D7 system in Type IIB string theory, whose gravity dual is given by the AdS soliton background with probe D7-branes attaching to the AdS boundary along the defects. We holographically renormalize the free energy of the defect system with sources, from which we obtain the correlation functions for certain operators naturally associated to these defects. We find interesting phase transitions when the separation of the defects as well as the temperature are varied. We also discuss some implications for the Fractional Quantum Hall Effect and for two-dimensional QCD.
Fabrication Technique of Holographic Sight
Institute of Scientific and Technical Information of China (English)
LIN Ling; LIU Shou; ZHANG Xiang-su
2005-01-01
There are several types of sights used for small arms. All of them have advantages and disadvantages. A new type of sight-holographic sight-is introduced in the paper, with the emphasis on the fabrication technique of the hologram which is the most important part in the sight. A Gaussian dot and a reticle pattern are recorded in the hologram. When illuminated by a laser diode, the virtual images of the dot and the reticle pattern for aiming are observed through the hologram. Compared with other sights, the holographic sight provides quicker, more accurate and covert aiming at moving targets, particularly in close quarter combat situations. It significantly improves the capability of small arms used in close quarter fighting in all weathers.
Holographic Mutual Information is Monogamous
Hayden, Patrick; Maloney, Alexander
2013-01-01
We identify a special information-theoretic property of quantum field theories with holographic duals: the mutual informations among arbitrary disjoint spatial regions A,B,C obey the inequality I(A:BC) >= I(A:B)+I(A:C), provided entanglement entropies are given by the Ryu-Takayanagi formula. Inequalities of this type are known as monogamy relations and are characteristic of measures of quantum entanglement. This suggests that correlations in holographic theories arise primarily from entanglement rather than classical correlations. We also show that the Ryu-Takayanagi formula is consistent with all known general inequalities obeyed by the entanglement entropy, including an infinite set recently discovered by Cadney, Linden, and Winter; this constitutes strong evidence in favour of its validity.
Holographic mutual information is monogamous
Hayden, Patrick; Headrick, Matthew; Maloney, Alexander
2013-02-01
We identify a special information-theoretic property of quantum field theories with holographic duals: the mutual informations among arbitrary disjoint spatial regions A, B, C obey the inequality I(A∶B∪C)≥I(A∶B)+I(A∶C), provided entanglement entropies are given by the Ryu-Takayanagi formula. Inequalities of this type are known as monogamy relations and are characteristic of measures of quantum entanglement. This suggests that correlations in holographic theories arise primarily from entanglement rather than classical correlations. We also show that the Ryu-Takayanagi formula is consistent with all known general inequalities obeyed by the entanglement entropy, including an infinite set recently discovered by Cadney et al.; this constitutes strong evidence in favor of its validity.
Holographic quenches with a gap
da Silva, Emilia; Lopez, Esperanza; Mas, Javier; Serantes, Alexandre
2016-06-01
In order to holographically model quenches with a gapped final hamiltonian, we consider a gravity-scalar theory in anti-de Sitter space with an infrared hard wall. We allow a time dependent profile for the scalar field at the wall. This induces an energy exchange between bulk and wall and generates an oscillating scalar pulse. We argue that such backgrounds are the counterpart of quantum revivals in the dual field theory. We perform a qualitative comparison with the quench dynamics of the massive Schwinger model, which has been recently analyzed using tensor network techniques. Agreement is found provided the width of the oscillating scalar pulse is inversely linked to the energy density communicated by the quench. We propose this to be a general feature of holographic quenches.
Electromagnetically Induced Quantum Holographic Imaging
Qiu, Tian-Hui; Xie, Min; Ma, Hong-Yang; Zheng, Chun-Hong; Chen, Li-Bo
2016-05-01
We study the quantum holographic imaging of one-dimensional electromagnetically induced grating created by a strong standing wave in an atomic medium. Entangled photon pairs, generated in a spontaneous parametric down-conversion process, are employed as the imaging light to realize coincidence recording. By theoretical analysis and numerical simulation, we find that both the amplitude and phase information of the object can be imaged with the characteristic of imaging nonlocally and of arbitrarily controllable image variation in size.
Holographic multiverse and conformal invariance
Energy Technology Data Exchange (ETDEWEB)
Garriga, Jaume [Departament de Física Fonamental i Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, 08193 Barcelona (Spain); Vilenkin, Alexander, E-mail: jaume.garriga@ub.edu, E-mail: vilenkin@cosmos.phy.tufts.edu [Institute of Cosmology, Department of Physics and Astronomy, Tufts University, 212 College Ave., Medford, MA 02155 (United States)
2009-11-01
We consider a holographic description of the inflationary multiverse, according to which the wave function of the universe is interpreted as the generating functional for a lower dimensional Euclidean theory. We analyze a simple model where transitions between inflationary vacua occur through bubble nucleation, and the inflating part of spacetime consists of de Sitter regions separated by thin bubble walls. In this model, we present some evidence that the dual theory is conformally invariant in the UV.
Generalized Superconductors and Holographic Optics
Mahapatra, Subhash; Sarkar, Tapobrata
2013-01-01
We study generalized holographic s-wave superconductors in four dimensional R-charged black hole backgrounds, in the probe limit. We first establish the superconducting nature of the boundary theory, and then study its optical properties. Numerical analysis indicates that a negative index of refraction appears at low frequencies in the theory, for certain temperature ranges, for specific values of the charge parameter. The corresponding cut-off values for these are numerically established in several cases.
Holographic superconductors with Weyl corrections
Momeni, Davood; Raza, Muhammad; Myrzakulov, Ratbay
2016-10-01
A quick review on the analytical aspects of holographic superconductors (HSCs) with Weyl corrections has been presented. Mainly, we focus on matching method and variational approaches. Different types of such HSC have been investigated — s-wave, p-wave and Stúckelberg ones. We also review the fundamental construction of a p-wave type, in which the non-Abelian gauge field is coupled to the Weyl tensor. The results are compared from numerics to analytical results.
Holographic renormalization in teleparallel gravity
Energy Technology Data Exchange (ETDEWEB)
Krssak, Martin [Universidade Estadual Paulista, Instituto de Fisica Teorica, Sao Paulo, SP (Brazil)
2017-01-15
We consider the problem of IR divergences of the action in the covariant formulation of teleparallel gravity in asymptotically Minkowski spacetimes. We show that divergences are caused by inertial effects and can be removed by adding an appropriate surface term, leading to the renormalized action. This process can be viewed as a teleparallel analog of holographic renormalization. Moreover, we explore the variational problem in teleparallel gravity and explain how the variation with respect to the spin connection should be performed. (orig.)
Constructive use of holographic projections
Energy Technology Data Exchange (ETDEWEB)
Schroer, Bert [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Institut fuer Theoretische Physik der FU, Berlin (Germany)
2008-07-01
Revisiting the old problem of existence of interacting models of QFT with new conceptual ideas and mathematical tools, one arrives at a novel view about the nature of QFT. The recent success of algebraic methods in establishing the existence of factorizing models suggests new directions for a more intrinsic constructive approach beyond Lagrangian quantization. Holographic projection simplifies certain properties of the bulk theory and hence is a promising new tool for these new attempts. (author)
Holographic interferometry in construction analysis
Energy Technology Data Exchange (ETDEWEB)
Hartikainen, T.
1995-12-31
In this work techniques for visualizing phase and opaque objects by ruby laser interferometry are introduced. A leakage flow as a phase object is studied by holographic interferometry and the intensity distribution of the interferograms presenting the leakage flow are computer-simulated. A qualitative and quantitative analysis of the leakage flow is made. The analysis is based on the experimental and theoretical results presented in this work. The holographic setup and the double pass method for visualizing leakage flow are explained. A vibrating iron plate is the opaque object. Transient impact waves are generated by a pistol bullet on the iron plate and visualized by holographic interferometry. An apparatus with the capability of detecting and calculating the delays necessary for laser triggering is introduced. A time series of interferograms presenting elastic wave formation in an iron plate is shown. A computer-simulation of the intensity distributions of these interferograms is made. An analysis based on the computer-simulation and the experimental data of the transient elastic wave is carried out and the results are presented. (author)
Towards Holographic Quantum Energy Teleportation
Giataganas, Dimitrios; Liu, Pei-Hua
2016-01-01
We propose a protocol of quantum energy teleportation (QET) for holographic conformal field theory (CFT) in 3-dimensional anti-de Sitter space with or without black hole. A generic QET protocol contains two steps: (i) Alice injects the energy into ground state by performing local measurement; (ii) the distant Bob extracts energy by performing local operation according to Alice's measurement outcome. In our holographic protocol, we mimic the step (i) by local projection of an interval of CFT ground state into an excited state described by Banados geometry. For the step (ii) we adopt the surface/state duality to evaluate the energy extraction by local deformation of UV surface as the holographic dual of Bob's local unitary operations. Our results show that this protocol always gains energy extraction. Moreover, the ratio of Bob's extraction energy density to the energy density of the excited state after Alice's local projection is a positive semi-definite and bounded function of the UV surface deformation profi...
Monitoring by holographic radar systems
Catapano, Ilaria; Crocco, Lorenzo; Affinito, Antonio; Gennarelli, Gianluca; Soldovieri, Francesco
2013-04-01
Nowadays, radar technology represents a significant opportunity to collect useful information for the monitoring and conservation of critical infrastructures. Radar systems exploit the non-invasive interaction between the matter and the electromagnetic waves at microwave frequencies. Such an interaction allows obtaining images of the region under test from which one can infer the presence of potential anomalies such as deformations, cracks, water infiltrations, etc. This information turns out to be of primary importance in practical scenarios where the probed structure is in a poor state of preservation and renovation works must be planned. In this framework, the aim of this contribution is to describe the potentialities of the holographic radar Rascan 4/4000, a holographic radar developed by Remote Sensing Laboratory of Bauman Moscow State Technical University, as a non-destructive diagnostic tool capable to provide, in real-time, high resolution subsurface images of the sounded structure [1]. This radar provides holograms of hidden anomalies from the amplitude of the interference signal arising between the backscattered signal and a reference signal. The performance of the holographic radar is appraised by means of several experiments. Preliminary tests concerning the imaging below the floor and inside wood structures are carried out in controlled conditions at the Electromagnetic Diagnostic Laboratory of IREA-CNR. After, with reference to bridge monitoring for security aim, the results of a measurement campaign performed on the Musmeci bridge are presented [2]. Acknowledgments This research has been performed in the framework of the "Active and Passive Microwaves for Security and Subsurface imaging (AMISS)" EU 7th Framework Marie Curie Actions IRSES project (PIRSES-GA-2010-269157). REFERENCES [1] S. Ivashov, V. Razevig, I. Vasilyev, A. Zhuravlev, T. Bechtel, L. Capineri, The holographic principle in subsurface radar technology, International Symposium to
Holographic preamplifier for a quantum amplifier
Energy Technology Data Exchange (ETDEWEB)
Zemskov, K.I.; Kazarian, M.A.; Orlova, N.G.; Liuksiutov, S.F.; Odulov, S.G.
1988-08-01
Successive amplification of a weak optical signal was realized experimentally in holographic and quantum amplifiers. The signal was a coherent one with an intensity less than the actual noise of the copper-vapor active medium; the technique involved the use of a coherent holographic preamplifier based on a lithium niobate/sodium photorefractive crystal. 8 references.
The surface density of holographic entropy
Kiselev, V V
2010-01-01
On the basis of postulates for the holographic description of gravity and the introduction of entropic force in E. Verlinde's article [arXiv:1001.0785], for static sources we derive the universal law: the entropy of a holographic screen is equal to quarter of its area in the Planck system of units.
The holographic screen at low temperatures
Kiselev, V V
2010-01-01
A permissible spectrum of transverse vibrations for the holographic screen modifies both a distribution of thermal energy over bits at low temperatures and the law of gravitation at small accelerations of free fall in agreement with observations of flat rotation curves in spiral galaxies. This modification relates holographic screen parameters in de Sitter space-time with the Milgrom acceleration in MOND.
Imaging characteristics of a volume holographic lens
Yang, Jing; Jiang, Zhu-qing; Xu, Zhi-qiang; Liu, Shao-jie; Sun, Ya-jun; Tao, Shi-quan
2009-07-01
A volume holographic grating lens can reconstruct the three-dimensional information by conducting multiple optical slicing of an object based on Bragg selectivity of the volume holographic grating. In this paper, we employ the point-spread function of volume holographic imaging system to theoretically analyze its imaging resolution. In the experiments, the volume holographic gratings are made with a spherical reference (SR) and a planar reference (PR), respectively, and used as volume holographic imaging lens in our imaging system. The longitudinal and lateral defocusing characteristics of volume holographic lens with SR and with PR are investigated experimentally by displacing the interested objects from original reference location, respectively. The effects of the parameters of the volume holographic lens on the longitudinal and lateral resolution are also discussed. The experimental results show that increasing the size of the volume holographic lens can improve the depth resolution, and in particular, it has greater influence on SR VHI. The lateral selectivity of SR VHI is more sensitive than that of PR VHI, and the Bragg degenerate diffraction of PR VHI on the y axis is obviously observed.
Ultra-High Capacity Holographic Memories
2007-11-02
Momtahan, G. H. Cadena , and A. Adibi, "Sensitivity variation in two-center holographic recording," submitted to Op’tics Letters. 7. H. Pishro-Nik and F...34 Optics in the Southeast Meeting, Huntsville, AL, October 2002. 6. 0. Momtahan, G. H. Cadena , and A. Adibi, "Stabilized Two-Center Holographic
Perovskite Materials: Solar Cell and Optoelectronic Applications
Energy Technology Data Exchange (ETDEWEB)
Yang, Bin [ORNL; Geohegan, David B [ORNL; Xiao, Kai [ORNL
2017-01-01
Hybrid organometallic trihalide perovskites are promising candidates in the applications for next-generation, high-performance, low-cost optoelectronic devices, including photovoltaics, light emitting diodes, and photodetectors. Particularly, the solar cells based on this type of materials have reached 22% lab scale power conversion efficiency in only about seven years, comparable to the other thin film photovoltaic technologies. Hybrid perovskite materials not only exhibit superior optoelectronic properties, but also show many interesting physical properties such as ion migration and defect physics, which may allow the exploration of more device functionalities. In this article, the fundamental understanding of the interrelationships between crystal structure, electronic structure, and material properties is discussed. Various chemical synthesis and processing methods for superior device performance in solar cells and optoelectronic devices are reviewed.
Contemporary optoelectronics materials, metamaterials and device applications
Sukhoivanov, Igor
2016-01-01
This book presents a collection of extended contributions on the physics and application of optoelectronic materials and metamaterials. The book is divided into three parts, respectively covering materials, metamaterials and optoelectronic devices. Individual chapters cover topics including phonon-polariton interaction, semiconductor and nonlinear organic materials, metallic, dielectric and gyrotropic metamaterials, singular optics, parity-time symmetry, nonlinear plasmonics, microstructured optical fibers, passive nonlinear shaping of ultrashort pulses, and pulse-preserving supercontinuum generation. The book contains both experimental and theoretical studies, and each contribution is a self-contained exposition of a particular topic, featuring an extensive reference list. The book will be a useful resource for graduate and postgraduate students, researchers and engineers involved in optoelectronics/photonics, quantum electronics, optics, and adjacent areas of science and technology.
Holographic Complexity for Time-Dependent Backgrounds
Momeni, Davood; Bahamonde, Sebastian; Myrzakulov, Ratbay
2016-01-01
In this paper, we will analyse the holographic complexity for time-dependent asymptotically $AdS$ geometries. We will first use a covariant zero mean curvature slicing of the time-dependent bulk geometries, and then use this co-dimension one spacelike slice of the bulk spacetime to define a co-dimension two minimal surface. The time-dependent holographic complexity will be defined using the volume enclosed by this minimal surface. This time-dependent holographic complexity will reduce to the usual holographic complexity for static geometries. We will analyse the time-dependence as a perturbation of the asymptotically $AdS$ geometries. Thus, we will obtain time-dependent asymptotically $AdS$ geometries, and we will calculate the holographic complexity for such a time-dependent geometries.
New recording materials for the holographic industry
Jurbergs, David; Bruder, Friedrich-Karl; Deuber, Francois; Fäcke, Thomas; Hagen, Rainer; Hönel, Dennis; Rölle, Thomas; Weiser, Marc-Stephan; Volkov, Andy
2009-02-01
This paper describes a new class of recording materials for volume holographic applications suitable to meet commercial manufacturing needs. These next-generation holographic photopolymers have the ability to satisfy the unmet demand for color and depth tuning that is only possible with volume holograms. Unlike earlier holographic photopolymers, these new materials offer the advantages of no chemical or thermal processing combined with low shrinkage and detuning. Furthermore, these materials exhibit high transparency, a high resolution of more than 5000 lines/mm and are environmentally robust. Bayer MaterialScience plans to commercialize these materials, which combine excellent holographic characteristics with compatibility to mass-production processes. In this paper, we will briefly discuss the potential markets and applications for a new photopolymer, describe the attributes of this new class of photopolymers, relate their ease of use in holographic recording, and discuss potential applications of such materials..
耳内镜在耳科疾病诊治中的应用效果分析%Otoscope Application for Diagnosis and Treatment of Otology Disease
Institute of Scientific and Technical Information of China (English)
2013-01-01
Objective:To explore otoscope application for diagnosis and treatment of otology disease.Methods:206 cases patients with the otology disease were retrospective analyzed from January 2010 to November 2012,through the different diameter and Angle ear endoscope,the external auditory meatus,tympanic membrane,middle ear make a diagnosis and give treatment or minimally invasive surgical treatment.Results:Through the endoscopic check 206 patients (216 ears),chronic otitis media accounts for 75 cases.Secretory otitis media of 52 cases.Tympanic membrane perforation patients of 45 cases.External auditory meatus foreign body of 44 cases.Endoscopic treatment after January patients were followed up,external auditory meatus foreign body of the total effective rate was 100%,secretory otitis media is 96.15%;Chronic otitis media is 94.67%;Tympanic membrane perforation is 88.89%.Conclusion:Endoscopic examination can improve middle ear disease diagnosis accuracy;In the endoscopic,minimally invasive surgical curative effect is reliable.% 目的：探讨耳内镜在耳科疾病诊治中应用效果。方法：回顾性分析我院自2010年1月~2012年11月间收治的耳科疾病患者206例，采用不同直径及角度的耳内镜对外耳道、鼓膜、中耳等进行检查或微创手术治疗。结果：用耳内镜检查206例(216耳)，慢性中耳炎75例；分泌性中耳炎52例；鼓膜穿孔患者45例；外耳道异物44例，在内镜下积极治疗后外耳道异物的总有效率为100%，分泌性中耳炎为96.15%；慢性中耳炎为94.67%；鼓膜穿孔为88.89%。结论：耳内镜下检查能够提高中耳疾病诊断准确率；在耳内镜下行微创手术疗效可靠。
Electromagnetic Theory for Microwaves and Optoelectronics
Zhang, Keqian
2007-01-01
This book is a first year graduate text on electromagnetic fields and waves. At the same time it serves as a useful reference for researchers and engineers in the areas of microwaves and optoelectronics. Following the presentation of the physical and mathematical foundations of electromagnetic theory, the book discusses the field analysis of electromagnetic waves confined in material boundaries, or so-called guided waves, electromagnetic waves in the dispersive media and anisotropic media, Gaussian beams and scalar diffraction theory. The theories and methods presented in the book are foundations of wireless engineering, microwave and millimeter wave techniques, optoelectronics and optical fiber communication.
Optoelectronic line transmission an introduction to fibre optics
Tricker, Raymond L
2013-01-01
Optoelectronic Line Transmission: An Introduction to Fibre Optics presents a basic introduction as well as a background reference manual on fiber optic transmission. The book discusses the basic principles of optical line transmission; the advantages and disadvantages of optical fibers and optoelectronic signalling; the practical applications of optoelectronics; and the future of optoelectronics. The text also describes the theories of optical line transmission; fibers and cables for optical transmission; transmitters including light-emitting diodes and lasers; and receivers including photodi
Holographic superconductors with hyperscaling violation
Fan, ZhongYing
2013-01-01
We investigate holographic superconductors in asympototically geometries with hyperscaling violation. The mass of the scalar field decouples from the UV dimension of the dual scalar operator and can be chosen as negative as we want, without disturbing the Breitenlohner-Freedman bound. We first numerically find that the scalar condenses below a critical temperature and a gap opens in the real part of the conductivity, indicating the onset of superconductivity. We further analytically explore the effects of the hyperscaling violation on the superconducting transition temperature. We find that the critical temperature increases with the increasing of hyperscaling violation.
The holographic supersymmetric Casimir energy
Genolini, Pietro Benetti; Martelli, Dario; Sparks, James
2016-01-01
We consider a general class of asymptotically locally AdS_5 solutions of minimal gauged supergravity, that are dual to superconformal field theories on curved backgrounds S^1 x M_3 preserving two supercharges. We demonstrate that standard holographic renormalization corresponds to a scheme that breaks supersymmetry. We propose new boundary terms that restore supersymmetry, and show that for smooth solutions with topology S^1 x R^4 the improved on-shell action reproduces both the supersymmetric Casimir energy and the field theory BPS relation between charges.
Holographic Complexity Equals Bulk Action?
Brown, Adam R.; Roberts, Daniel A.; Susskind, Leonard; Swingle, Brian; Zhao, Ying
2016-05-01
We conjecture that the quantum complexity of a holographic state is dual to the action of a certain spacetime region that we call a Wheeler-DeWitt patch. We illustrate and test the conjecture in the context of neutral, charged, and rotating black holes in anti-de Sitter spacetime, as well as black holes perturbed with static shells and with shock waves. This conjecture evolved from a previous conjecture that complexity is dual to spatial volume, but appears to be a major improvement over the original. In light of our results, we discuss the hypothesis that black holes are the fastest computers in nature.
Theta angle in holographic QCD
Jarvinen, Matti
2016-01-01
V-QCD is a class of effective holographic models for QCD which fully includes the backreaction of quarks to gluon dynamics. The physics of the theta-angle and the axial anomaly can be consistently included in these models. We analyze their phase diagrams over ranges of values of the quark mass, N_f/N_c, and theta, computing observables such as the topological susceptibility and the meson masses. At small quark mass, where effective chiral Lagrangians are reliable, they agree with the predictions of V-QCD.
Holographic d-wave superconductors
Kim, Keun-Young
2013-01-01
We construct top down models for holographic d-wave superfluids in which the order parameter is a charged spin two field in the bulk. Close to the transition temperature the condensed phase can be captured by a charged spin two field in an R-charged black hole background (downstairs picture) or equivalently by specific graviton perturbations of a spinning black brane (upstairs picture). We analyse the necessary conditions on the mass and the charge of the spin two field for a condensed phase to exist and we discuss the competition of the d-wave phase with other phases such as s-wave superfluids.
Holographic s+p Superconductors
Amado, Irene; Jimenez-Alba, Amadeo; Melgar, Luis; Landea, Ignacio Salazar
2014-01-01
We study the phase diagram of a holographic model realizing a U(2) global symmetry on the boundary and show that at low temperature a phase with both scalar s and vector p condensates exists. This is the s+p-wave phase where the global U(2) symmetry and also the spatial rotational symmetry are spontaneously broken. By studying the free energy we show that this phase is preferred when it exists. We also consider unbalanced configurations where a second chemical potential is turned on. They present a rich phase diagram characterized by the competition and coexistence of the s and p order parameters.
The holographic supersymmetric Casimir energy
Benetti Genolini, Pietro; Cassani, Davide; Martelli, Dario; Sparks, James
2017-01-01
We consider a general class of asymptotically locally AdS5 solutions of minimal gauged supergravity, which are dual to superconformal field theories on curved backgrounds S1×M3 preserving two supercharges. We demonstrate that standard holographic renormalization corresponds to a scheme that breaks supersymmetry. We propose new boundary terms that restore supersymmetry, and show that for smooth solutions with topology S1×R4 the improved on-shell action reproduces both the supersymmetric Casimir energy and the field theory supersymmetric relation between charges.
Generalized superconductors and holographic optics
Energy Technology Data Exchange (ETDEWEB)
Mahapatra, Subhash; Phukon, Prabwal; Sarkar, Tapobrata [Department of Physics, Indian Institute of Technology,Kanpur 208016 (India)
2014-01-24
We study generalized holographic s-wave superconductors in four dimensional R-charged black hole and Lifshitz black hole backgrounds, in the probe limit. We first establish the superconducting nature of the boundary theories, and then study their optical properties. Numerical analysis indicates that a negative Depine-Lakhtakia index may appear at low frequencies in the theory dual to the R-charged black hole, for certain temperature ranges, for specific values of the charge parameter. The corresponding cut-off values for these are numerically established in several cases. Such effects are seen to be absent in the Lifshitz background where this index is always positive.
Holographic Thermalization with Weyl Corrections
Dey, Anshuman; Sarkar, Tapobrata
2015-01-01
We consider holographic thermalization in the presence of a Weyl correction in five dimensional AdS space. We numerically analyze the time dependence of the two point correlation functions and the expectation values of rectangular Wilson loops in the boundary field theory. The subtle interplay between the Weyl coupling constant and the chemical potential is studied in detail. An outcome of our analysis is the appearance of a swallow tail behaviour in the thermalization curve, and we give evidence that this might indicate distinct physical situations relating to different length scales in the problem.
Semi-holographic model revisited
Cárdenas, Víctor H; Magaña, Juan
2013-01-01
In a recent work Zhang, Li and Noh [Phys. Lett. B {\\bf 694}, 177 (2010)]proposed a model for dark energy assuming this component strictly obeys the holographic principle. They performed a dynamical system analysis, finding a scaling solution which is helpful to solve the coincidence problem. However they need explicitly a cosmological constant. In this paper we derive an explicit analytical solution, without $\\Lambda$, that shows agreement with the Supernovae data. However this solution is not physical because violate all the energy conditions.
Photoemission from optoelectronic materials and their nanostructures
Ghatak, Kamakhya Prasad; Bhattacharya, Sitangshu
2009-01-01
This monograph investigates photoemission from optoelectronic materials and their nanostructures. It contains open-ended research problems which form an integral part of the text and are useful for graduate courses as well as aspiring Ph.D.'s and researchers..
Trends in optoelectronic perimeter security sensors
Szustakowski, Mieczyslaw; Ciurapinski, Wiesław M.; Zyczkowski, Marek
2007-10-01
New trends in development of optoelectronic and radar systems with mixed technologies for detection, identification and visualization for critical infrastructure protection are presented. Network-based communication as well as new algorithms of intelligent vision surveillance and image fusion is described.
Using optoelectronic sensors in the system PROTEUS
Zyczkowski, M.; Szustakowski, M.; Ciurapinski, W.; Piszczek, M.
2010-10-01
The paper presents the concept of optoelectronic devices for human protection in rescue activity. The system consists of an ground robots with predicted sensor. The multisensor construction of the system ensures significant improvement of security of using on-situ like chemical or explosive sensors. The article show a various scenario of use for individual sensor in system PROTEUS.
Polymer optoelectronic structures for retinal prosthesis.
Gautam, Vini; Narayan, K S
2014-01-01
This commentary highlights the effectiveness of optoelectronic properties of polymer semiconductors based on recent results emerging from our laboratory, where these materials are explored as artificial receptors for interfacing with the visual systems. Organic semiconductors based polymer layers in contact with physiological media exhibit interesting photophysical features, which mimic certain natural photoreceptors, including those in the retina. The availability of such optoelectronic materials opens up a gateway to utilize these structures as neuronal interfaces for stimulating retinal ganglion cells. In a recently reported work entitled "A polymer optoelectronic interface provides visual cues to a blind retina," we utilized a specific configuration of a polymer semiconductor device structure to elicit neuronal activity in a blind retina upon photoexcitation. The elicited neuronal signals were found to have several features that followed the optoelectronic response of the polymer film. More importantly, the polymer-induced retinal response resembled the natural response of the retina to photoexcitation. These observations open up a promising material alternative for artificial retina applications.
GaAs optoelectronic neuron arrays
Lin, Steven; Grot, Annette; Luo, Jiafu; Psaltis, Demetri
1993-01-01
A simple optoelectronic circuit integrated monolithically in GaAs to implement sigmoidal neuron responses is presented. The circuit integrates a light-emitting diode with one or two transistors and one or two photodetectors. The design considerations for building arrays with densities of up to 10,000/sq cm are discussed.
Moving through a multiplex holographic scene
Mrongovius, Martina
2013-02-01
This paper explores how movement can be used as a compositional element in installations of multiplex holograms. My holographic images are created from montages of hand-held video and photo-sequences. These spatially dynamic compositions are visually complex but anchored to landmarks and hints of the capturing process - such as the appearance of the photographer's shadow - to establish a sense of connection to the holographic scene. Moving around in front of the hologram, the viewer animates the holographic scene. A perception of motion then results from the viewer's bodily awareness of physical motion and the visual reading of dynamics within the scene or movement of perspective through a virtual suggestion of space. By linking and transforming the physical motion of the viewer with the visual animation, the viewer's bodily awareness - including proprioception, balance and orientation - play into the holographic composition. How multiplex holography can be a tool for exploring coupled, cross-referenced and transformed perceptions of movement is demonstrated with a number of holographic image installations. Through this process I expanded my creative composition practice to consider how dynamic and spatial scenes can be conveyed through the fragmented view of a multiplex hologram. This body of work was developed through an installation art practice and was the basis of my recently completed doctoral thesis: 'The Emergent Holographic Scene — compositions of movement and affect using multiplex holographic images'.
Holographic entanglement entropy on generic time slices
Kusuki, Yuya; Takayanagi, Tadashi; Umemoto, Koji
2017-06-01
We study the holographic entanglement entropy and mutual information for Lorentz boosted subsystems. In holographic CFTs at zero and finite temperature, we find that the mutual information gets divergent in a universal way when the end points of two subsystems are light-like separated. In Lifshitz and hyperscaling violating geometries dual to non-relativistic theories, we show that the holographic entanglement entropy is not well-defined for Lorentz boosted subsystems in general. This strongly suggests that in non-relativistic theories, we cannot make a real space factorization of the Hilbert space on a generic time slice except the constant time slice, as opposed to relativistic field theories.
Order parameter fluctuations in the holographic superconductor
Plantz, N. W. M.; Stoof, H. T. C.; Vandoren, S.
2017-03-01
We investigate the effect of order parameter fluctuations in the holographic superconductor. In particular, following an introduction to the concept of intrinsic dynamics and its implementation within holographic models, we compute the intrinsic spectral functions of the order parameter in both the normal and the superconducting phase, using a fully backreacted bulk geometry. We also present a vector-like large-N version of the Ginzburg–Landau model that accurately describes our long-wavelength results in both phases. Our results indicate that the holographic superconductor describes a relativistic multi-component superfluid in the universal regime of the BEC–BCS crossover.
LDA optical setup using holographic imaging configuration
Ghosh, Abhijit; Nirala, A. K.
2015-11-01
This paper describes one of the possible ways for improving fringe quality at LDA measuring volume using a holographic imaging configuration consisting of a single hololens. For its comparative study with a conventional imaging configuration, a complete characterization of fringes formed at the measurement volume by both the configuration is presented. Results indicate the qualitative as well as quantitative improvement of the fringes formed at measurement volume by the holographic imaging configuration. Hence it is concluded that use of holographic imaging configuration for making LDA optical setup is a better choice than the conventional one.
Baryon Transition in Holographic QCD
Li, Siwen
2015-01-01
We propose a mechanism of holographic baryon transition in the Sakai-Sugimoto (SS) model: baryons in this model can jump to different states under the mediated effect of gravitons (or glueballs by holography). We consider a time-dependent gravitational perturbation from M5-brane solution of D=11 supergravity and by employing the relations between 11D M-theory and IIA string theory, we get its 10 dimensional counterpart in the SS model. Such a perturbation is received by the D4-branes wrapped on the $S^{4}$ part of the 10D background, namely the baryon vertex. Technically, baryons in the SS model are described by BPST instanton ansatz and their dynamics can be analyzed using the quantum mechanical system in the instanton's moduli space. In this way, different baryonic states are marked by quantum numbers of moduli space quantum mechanics. By holographic spirit, the gravitational perturbation enters the Hamiltonian as a time-dependent perturbation and it is this time-dependent perturbative Hamiltonian produces ...
Bit threads and holographic entanglement
Freedman, Michael
2016-01-01
The Ryu-Takayanagi (RT) formula relates the entanglement entropy of a region in a holographic theory to the area of a corresponding bulk minimal surface. Using the max flow-min cut principle, a theorem from network theory, we rewrite the RT formula in a way that does not make reference to the minimal surface. Instead, we invoke the notion of a "flow", defined as a divergenceless norm-bounded vector field, or equivalently a set of Planck-thickness "bit threads". The entanglement entropy of a boundary region is given by the maximum flux out of it of any flow, or equivalently the maximum number of bit threads that can emanate from it. The threads thus represent entanglement between points on the boundary, and naturally implement the holographic principle. As we explain, this new picture clarifies several conceptual puzzles surrounding the RT formula. We give flow-based proofs of strong subadditivity and related properties; unlike the ones based on minimal surfaces, these proofs correspond in a transparent manner...
Holographic duals of Boundary CFTs
Chiodaroli, Marco; Gutperle, Michael
2012-01-01
New families of regular half-BPS solutions to 6-dimensional Type 4b supergravity with $m$ tensor multiplets are constructed exactly. Their space-time consists of $AdS_2 \\times S^2$ warped over a Riemann surface with an arbitrary number of boundary components, and arbitrary genus. The solutions have an arbitrary number of asymptotic $AdS_3 \\times S^3$ regions. In addition to strictly single-valued solutions to the supergravity equations whose scalars live in the coset $SO(5,m)/SO(5)\\times SO(m)$, we also construct stringy solutions whose scalar fields are single-valued up to transformations under the $U$-duality group $SO(5,m;\\bZ)$, and live in the coset $SO(5,m;\\bZ)\\backslash SO(5,m)/SO(5)\\times SO(m)$. We argue that these Type 4b solutions are holographically dual to general classes of interface and boundary CFTs arising at the juncture of the end-points of 1+1-dimensional bulk CFTs. We evaluate their corresponding holographic entanglement and boundary entropy, and discuss their brane interpretation. We conj...
Exploring holographic Composite Higgs models
Croon, Djuna; Huber, Stephan J; Sanz, Veronica
2015-01-01
Simple Composite Higgs models predict new vector-like fermions not too far from the electroweak scale, yet LHC limits are now sensitive to the TeV scale. Motivated by this tension, we explore the holographic dual of the minimal model, MCHM5, to understand how far naive 4D predictions are from their 5D duals. Interestingly, we find that the usual hierarchy among the vector-like quarks is not generic, hence ameliorating the tuning issue. We also find that lowering the hierarchy of scales in the 5D picture allows for heavier top partners, while keeping the mass of the Higgs boson at its observed value. In the 4D dual this corresponds to increasing the number of colours N. Furthermore, in anticipation of the ongoing efforts at the LHC to put bounds on the top Yukawa, we demonstrate that deviations from the SM can be suppressed or enhanced with respect to what is expected from mere symmetry arguments in 4D. We conclude that the 5D holographic realisation of the MCHM5 with a small hierarchy of scales may not in ten...
Unbalanced Holographic Superconductors and Spintronics
Bigazzi, Francesco; Musso, Daniele; Fokeeva, Natalia Pinzani; Seminara, Domenico
2011-01-01
We present a minimal holographic model for s-wave superconductivity with unbalanced Fermi mixtures, in 2+1 dimensions at strong coupling. The breaking of a U(1)_A "charge" symmetry is driven by a non-trivial profile for a charged scalar field in a charged asymptotically AdS_4 black hole. The chemical potential imbalance is implemented by turning on the temporal component of a U(1)_B "spin" field under which the scalar field is uncharged. We study the phase diagram of the model and comment on the eventual (non) occurrence of LOFF-like inhomogeneous superconducting phases. Moreover, we study "charge" and "spin" transport, implementing a holographic realization (and a generalization thereof to superconducting setups) of Mott's two-current model which provides the theoretical basis of modern spintronics. Finally we comment on possible string or M-theory embeddings of our model and its higher dimensional generalizations, within consistent Kaluza-Klein truncations and brane-anti brane setups.
Bit Threads and Holographic Entanglement
Freedman, Michael; Headrick, Matthew
2016-11-01
The Ryu-Takayanagi (RT) formula relates the entanglement entropy of a region in a holographic theory to the area of a corresponding bulk minimal surface. Using the max flow-min cut principle, a theorem from network theory, we rewrite the RT formula in a way that does not make reference to the minimal surface. Instead, we invoke the notion of a "flow", defined as a divergenceless norm-bounded vector field, or equivalently a set of Planck-thickness "bit threads". The entanglement entropy of a boundary region is given by the maximum flux out of it of any flow, or equivalently the maximum number of bit threads that can emanate from it. The threads thus represent entanglement between points on the boundary, and naturally implement the holographic principle. As we explain, this new picture clarifies several conceptual puzzles surrounding the RT formula. We give flow-based proofs of strong subadditivity and related properties; unlike the ones based on minimal surfaces, these proofs correspond in a transparent manner to the properties' information-theoretic meanings. We also briefly discuss certain technical advantages that the flows offer over minimal surfaces. In a mathematical appendix, we review the max flow-min cut theorem on networks and on Riemannian manifolds, and prove in the network case that the set of max flows varies Lipshitz continuously in the network parameters.
Randall-Sundrum vs. Holographic Braneworld
Bilic, Neven
2016-01-01
A mapping between two braneworld cosmologies -- Randall-Sundrum and holographic -- is explicitly constructed. The cosmologies are governed by the appropriate modified Friedman equations. A relationship between the corresponding Hubble rates is established.
G-corrected holographic dark energy model
Malekjani, M
2013-01-01
Here we investigate the holographic dark energy model in the framework of FRW cosmology where the Newtonian gravitational constant,$G$, is varying with cosmic time. Using the complementary astronomical data which support the time dependency of $G$, the evolutionary treatment of EoS parameter and energy density of dark energy model are calculated in the presence of time variation of $G$. It has been shown that in this case, the phantom regime can be achieved at the present time. We also calculate the evolution of $G$- corrected deceleration parameter for holographic dark energy model and show that the dependency of $G$ on the comic time can influence on the transition epoch from decelerated expansion to the accelerated phase. Finally we perform the statefinder analysis for $G$- corrected holographic model and show that this model has a shorter distance from the observational point in $s-r$ plane compare with original holographic dark energy model.
Hybrid holographic non-destructive test system
Kurtz, R. L. (Inventor)
1978-01-01
An automatic hybrid holographic non-destructive testing (HNDT) method and system capable of detecting flaws or debonds contained within certain materials are described. This system incorporates the techniques of optical holography, acoustical/optical holography and holographic correlation in determining the structural integrity of a test object. An automatic processing system including a detector and automatic data processor is used in conjunction with the three holographic techniques for correlating and interpreting the information supplied by the non-destructive systems. The automatic system also includes a sensor which directly translates an optical data format produced by the holographic techniques into electrical signals and then transmits this information to a digital computer for indicating the structural properties of the test object. The computer interprets the data gathered and determines whether further testing is necessary as well as the format of this new testing procedure.
Some applications of holographic interferometry in biomechanics
Ebbeni, Jean P. L.
1992-03-01
Holographic interferometry is well adapted for the determination of 2D strain fields in osseous structures. The knowledge of those strain fields is important for the understanding of structure behavior such as arthrosis.
Holographic tachyon model of dark energy
Setare, M.R.
2007-01-01
In this paper we consider a correspondence between the holographic dark energy density and tachyon energy density in FRW universe. Then we reconstruct the potential and the dynamics of the tachyon field which describe tachyon cosmology.
Strongly interacting matter from holographic QCD model
Chen, Yidian; Huang, Mei
2016-01-01
We introduce the 5-dimension dynamical holographic QCD model, which is constructed in the graviton-dilaton-scalar framework with the dilaton background field $\\Phi$ and the scalar field $X$ responsible for the gluodynamics and chiral dynamics, respectively. We review our results on the hadron spectra including the glueball and light meson spectra, QCD phase transitions and transport properties in the framework of the dynamical holographic QCD model.
Soft wall model for a holographic superconductor
Energy Technology Data Exchange (ETDEWEB)
Afonin, S.S.; Pusenkov, I.V. [Saint Petersburg State University, St.Petersburg (Russian Federation)
2016-06-15
We consider the soft wall holographic approach for description of the high-T{sub c} superconductivity. In comparison with the existing bottom-up holographic superconductors, the proposed approach is more phenomenological and does not describe the superconducting phase transition. On the other hand, technically it is simpler and has more freedom for fitting the conductivity properties of the real high-T{sub c} materials in the superconducting phase. Some examples of emerging models are analyzed. (orig.)
Soft wall model for a holographic superconductor
Afonin, S S
2015-01-01
We apply the soft wall holographic model from hadron physics to a description of the high-$T_c$ superconductivity. In comparison with the existing bottom-up holographic superconductors, the proposed approach is more phenomenological. On the other hand, it is much simpler and has more freedom for fitting the conductivity properties of the real high-$T_c$ materials. We demonstrate some examples of emerging models and discuss a possible origin of the approach.
Image Resolution of a Holographic System
1981-07-01
transfer function and linear systems theory to optical systems. This has also been applied to holographic image analysis (Refs. l I and 12). The...view point, the linear systems theory is applied in correlating the intensity distribution of a known point or line radiation source with the intensity...function of a holographic system, (2) a discussion of linear systems theory to allow a thorough description of a method for obtaining the line
Holographic Combiners for Head-Up Displays
1977-10-01
AFAL-TR-77 -110 S HOLOGRAPHIC COMBINERS FOR HEAD-UP DISPLAYS S Radar and Optics Division Environmental Research Institute of Michigan P.O. Box 8618...to 200. SECURITY CLASSIFICATION OF THIS PAGE(RWihen Data Entered) FOREWORD This report was prepared by the Radar and Optics Division of the...with fringes parallel to the surface......31 Figure 13. Raytrace through the F-4 HUD with a holographic combiner
Tunability of Nonuniform Reflection Holographic Filter
Institute of Scientific and Technical Information of China (English)
Shanhong You(游善红); Xinwan Li(李新碗); Jianhong Wu(吴建宏); Zongmin Yin(殷宗敏); Minxue Tang(唐敏学)
2003-01-01
The tunability of nonuniform reflection holographic filter is investigated theoretically and experimentally. It is shown that the reflection holographic filter has not only high optical density and narrow bandwidth, but also good tunability. The coupled wave theoretical model for uniform medium is compared with the model for nonuniform medium. It is identified that the coincidence of the theoretical results of the nonuniform model with the experimental results are better than that of the uniform model.
Materials for optoelectronic devices, OEICs and photonics
Energy Technology Data Exchange (ETDEWEB)
Schloetterer, H.; Quillec, M.; Greene, P.D.; Bertolotti, M. (eds.)
1991-01-01
The aim of the contributors in this volume is to give a current overview on the basic properties of nonlinear optical materials for optoelectronics and integrated optics. They provide a cross-linkage between different materials (III-V, II-VI, Si-Ge, etc.), various sample dimensions (from bulk crystals to quantum dots), and a range of techniques from growth (LPE to MOMBE) and for processing from surface passivation to ion beams. Major growth techniques and materials are discussed, including the sophisticated technologies required to exploit the exciting properties of low dimensional semiconductors. These proceedings will prove an invaluable guide to the current state of optoelectronic materials development, as well as indicating the growth techniques that will be in use around the year 2000.
Glass-Forming Organic Semiconductors for Optoelectronics
Directory of Open Access Journals (Sweden)
Aušra TOMKEVIČIENĖ
2011-11-01
Full Text Available Organic electronics and optoelectronics are newly emerging fields of science and technology that cover chemistry, physics, and materials science. Electronic and optoelectronic devices using organic materials are attractive because of the materials characteristics, potentially low cost, and capability of large-area, flexible device fabrication. Such devices as OLEDs, OPVs, and OFETs involve charge transport as a main process in their operation processes, and therefore, require high-performance charge-transporting materials. This review article focuses on charge-transporting materials for use in OLEDs, OPVs, and OFETs. We have tried to arrange the charge-transporting materials in order by classifying them on the basis of their molecular structures. Molecular design concepts for charge-transporting materials and their charge-transport properties are discussed.http://dx.doi.org/10.5755/j01.ms.17.4.767
Terahertz optoelectronics with surface plasmon polariton diode.
Vinnakota, Raj K; Genov, Dentcho A
2014-05-09
The field of plasmonics has experience a renaissance in recent years by providing a large variety of new physical effects and applications. Surface plasmon polaritons, i.e. the collective electron oscillations at the interface of a metal/semiconductor and a dielectric, may bridge the gap between electronic and photonic devices, provided a fast switching mechanism is identified. Here, we demonstrate a surface plasmon-polariton diode (SPPD) an optoelectronic switch that can operate at exceedingly large signal modulation rates. The SPPD uses heavily doped p-n junction where surface plasmon polaritons propagate at the interface between n and p-type GaAs and can be switched by an external voltage. The devices can operate at transmission modulation higher than 98% and depending on the doping and applied voltage can achieve switching rates of up to 1 THz. The proposed switch is compatible with the current semiconductor fabrication techniques and could lead to nanoscale semiconductor-based optoelectronics.
Performance Evaluation of an Integrated Optoelectronic Receiver
Directory of Open Access Journals (Sweden)
A. Vera-Marquina
2014-02-01
Full Text Available This work describes the optical and electrical characterization of an integrated optoelectronic receiver. The receiver is composed of a photodiode and a transimpedance amplifier, both fabricated in silicon technology using a 0.8 μm BiCMOS process. The total area occupied by the photodiode is of 10,000 μm2. In a first step, the generated photocurrent of the photodiode is measured for the wavelengths of 780 nm and 830 nm at different levels of optical power. In a second step, the responsivity and quantum efficiency parameters of the photodiode are computed. Finally, an electrical measurement including the transimpedance amplifier is achieved. A potential application for this optoelectronic receiver is on the first optical communications window.
Optoelectronic Devices Advanced Simulation and Analysis
Piprek, Joachim
2005-01-01
Optoelectronic devices transform electrical signals into optical signals and vice versa by utilizing the sophisticated interaction of electrons and light within micro- and nano-scale semiconductor structures. Advanced software tools for design and analysis of such devices have been developed in recent years. However, the large variety of materials, devices, physical mechanisms, and modeling approaches often makes it difficult to select appropriate theoretical models or software packages. This book presents a review of devices and advanced simulation approaches written by leading researchers and software developers. It is intended for scientists and device engineers in optoelectronics, who are interested in using advanced software tools. Each chapter includes the theoretical background as well as practical simulation results that help to better understand internal device physics. The software packages used in the book are available to the public, on a commercial or noncommercial basis, so that the interested r...
Multi-material optoelectronic fiber devices
Sorin, F.; Yan, Wei; Volpi, Marco; Page, Alexis G.; Nguyen Dang, Tung; Qu, Y.
2017-05-01
The recent ability to integrate materials with different optical and optoelectronic properties in prescribed architectures within flexible fibers is enabling novel opportunities for advanced optical probes, functional surfaces and smart textiles. In particular, the thermal drawing process has known a series of breakthroughs in recent years that have expanded the range of materials and architectures that can be engineered within uniform fibers. Of particular interest in this presentation will be optoelectronic fibers that integrate semiconductors electrically addressed by conducting materials. These long, thin and flexible fibers can intercept optical radiation, localize and inform on a beam direction, detect its wavelength and even harness its energy. They hence constitute ideal candidates for applications such as remote and distributed sensing, large-area optical-detection arrays, energy harvesting and storage, innovative health care solutions, and functional fabrics. To improve performance and device complexity, tremendous progresses have been made in terms of the integrated semiconductor architectures, evolving from large fiber solid-core, to sub-hundred nanometer thin-films, nano-filaments and even nanospheres. To bridge the gap between the optoelectronic fiber concept and practical applications however, we still need to improve device performance and integration. In this presentation we will describe the materials and processing approaches to realize optoelectronic fibers, as well as give a few examples of demonstrated systems for imaging as well as light and chemical sensing. We will then discuss paths towards practical applications focusing on two main points: fiber connectivity, and improving the semiconductor microstructure by developing scalable approaches to make fiber-integrated single-crystal nanowire based devices.
Holographic quenches and anomalous transport
Ammon, Martin; Jimenez-Alba, Amadeo; Macedo, Rodrigo P; Melgar, Luis
2016-01-01
We study the response of the chiral magnetic effect due to continuous quenches induced by time dependent electric fields within holography. Concretely, we consider a holographic model with dual chiral anomaly and compute the electric current parallel to a constant, homogeneous magnetic field and a time dependent electric field in the probe approximation. We explicitly solve the PDEs by means of pseudospectral methods in spatial and time directions and study the transition to an universal "fast" quench response. Moreover, we compute the amplitudes, i.e.,~residues of the quasi normal modes, by solving the (ODE) Laplace transformed equations. We investigate the possibility of considering the asymptotic growth rate of the amplitudes as a well defined notion of initial time scale for linearized systems. Finally, we highlight the existence of Landau level resonances in the electrical conductivity parallel to a magnetic field at finite frequency and show explicitly that these only appear in presence of the anomaly. ...
Defect CFTs and holographic multiverse
Energy Technology Data Exchange (ETDEWEB)
Fiol, Bartomeu, E-mail: bfiol@ub.edu [Departament de Física Fonamental i Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, 08193 Barcelona (Spain)
2010-07-01
We investigate some aspects of a recent proposal for a holographic description of the multiverse. Specifically, we focus on the implications on the suggested duality of the fluctuations of a bubble separating two universes with different cosmological constants. We do so by considering a similar problem in a 2+1 CFT with a codimension one defect, obtained by an M5-brane probe embedding in AdS{sub 4} × S{sup 7}, and studying its spectrum of fluctuations. Our results suggest that the kind of behavior required by the spectrum of bubble fluctuations is not likely to take place in defect CFTs with an AdS dual, although it might be possible if the defect supports a non-unitary theory.
Excited Baryons in Holographic QCD
Energy Technology Data Exchange (ETDEWEB)
de Teramond, Guy F.; /Costa Rica U.; Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins
2011-11-08
The light-front holographic QCD approach is used to describe baryon spectroscopy and the systematics of nucleon transition form factors. Baryon spectroscopy and the excitation dynamics of nucleon resonances encoded in the nucleon transition form factors can provide fundamental insight into the strong-coupling dynamics of QCD. The transition from the hard-scattering perturbative domain to the non-perturbative region is sensitive to the detailed dynamics of confined quarks and gluons. Computations of such phenomena from first principles in QCD are clearly very challenging. The most successful theoretical approach thus far has been to quantize QCD on discrete lattices in Euclidean space-time; however, dynamical observables in Minkowski space-time, such as the time-like hadronic form factors are not amenable to Euclidean numerical lattice computations.
MOND cosmology from holographic principle
Zhang, Hongsheng
2011-01-01
We derive the MOND cosmology which is uniquely corresponding to the original MOND in galaxies via holographic approach of gravity. It inherits the key merit of MOND, that is, it reduces the byronic matter and mysterious non-byronic dark matter (dark matter for short) in the standard cosmology into byronic matter only. For the first time we derive the critical parameter in MOND, i.e., the transition acceleration $a_c$ on cosmological scale. We thus solve the long-standing coincidence problem $a_c\\sim cH_{0}$. More interestingly, a term like age-graphic dark energy emerges naturally. In the frame of this MOND cosmology, we only need byronic matter to describe both dark matter and dark energy in standard cosmology.
Holographic Renormalization in Dense Medium
Directory of Open Access Journals (Sweden)
Chanyong Park
2014-01-01
describes a dense medium at finite temperature, is investigated in this paper. In a dense medium, two different thermodynamic descriptions are possible due to an additional conserved charge. These two different thermodynamic ensembles are classified by the asymptotic boundary condition of the bulk gauge field. It is also shown that in the holographic renormalization regularity of all bulk fields can reproduce consistent thermodynamic quantities and that the Bekenstein-Hawking entropy is nothing but the renormalized thermal entropy of the dual field theory. Furthermore, we find that the Reissner-Nordström AdS black brane is dual to a theory with conformal matter as expected, whereas a charged black brane with a nontrivial dilaton profile is mapped to a theory with nonconformal matter although its leading asymptotic geometry still remains as AdS space.
Soft Pomeron in Holographic QCD
Ballon-Bayona, Alfonso; Costa, Miguel S; Djurić, Marko
2016-01-01
We study the graviton Regge trajectory in Holographic QCD as a model for high energy scattering processes dominated by soft pomeron exchange. This is done by considering spin J fields from the closed string sector that are dual to glueball states of even spin and parity. In particular, we construct a model that governs the analytic continuation of the spin J field equation to the region of real J < 2, which includes the scattering domain of negative Maldelstam variable t. The model leads to approximately linear Regge trajectories and is compatible with the measured values of 1.08 for the intercept and 0.25 GeV$^{-2}$ for the slope of the soft pomeron. The intercept of the secondary pomeron trajectory is in the same region of the subleading trajectories, made of mesons, proposed by Donnachie and Landshoff, and should therefore be taken into account.
On Effective Holographic Mott Insulators
Baggioli, Matteo
2016-01-01
We present a class of holographic models that behave effectively as prototypes of Mott insulators, materials where electron-electron interactions dominate transport phenomena. The main ingredient in the gravity dual is that the gauge-field dynamics contains self-interactions by way of a particular type of non-linear electrodynamics. The electrical response in these models exhibits typical features of Mott-like states: i) the low-temperature DC conductivity is unboundedly low; ii) metal-insulator transitions appear by varying various parameters; iii) for large enough self-interaction strength, the conductivity can even decrease with increasing doping (density of carriers), which appears as a sharp manifestation of `traffic-jam'-like behaviour; iv) the insulating state becomes very unstable towards superconductivity at large enough doping. We exhibit some of the properties of the resulting insulator-superconductor transition, which is sensitive to the amount of disorder in a specific way. These models imply a c...
Holographic Cosmology from BIonic Solutions
Sepehri, Alireza; Setare, Mohammad Reza; Ali, Ahmed Farag
2015-01-01
In this paper, we will use a BIonic solution for analysing the holographic cosmology. A BIonic solution is a configuration of a D-brane and an anti-D-brane connected by a wormhole. A BIonic configuration can form due to a transition of fundamental black strings. After the BIon has formed, the wormhole in the BIon will act act as a channel for the energy to flow into the D3-brane. This will increase the degrees of freedom of the D3-brane causing inflation. The inflation will end when the wormhole gets annihilated. However, as the distance between the D3-brane and the anti-D3-brane reduces, tachyonic states get created. These tachyonic states will lead to the formation of a new wormhole. This new wormhole will again increasing the degrees of freedom on the D3-brane causing late time acceleration.
Holographic Software for Quantum Networks
Jaffe, Arthur; Wozniakowski, Alex
2016-01-01
We introduce diagrammatic protocols and holographic software for quantum information. We give a dictionary to translate between diagrammatic protocols and the usual algebraic protocols. In particular we describe the intuitive diagrammatic protocol for teleportation. We introduce the string Fourier transform $\\mathfrak{F}_{s}$ in quantum information, which gives a topological quantum computer. We explain why the string Fourier transform maps the zero particle state to the multiple-qudit resource state, which maximizes the entanglement entropy. We give a protocol to construct this $n$-qudit resource state $|Max \\rangle$, which uses minimal cost. We study Pauli $X,Y,Z$ matrices, and their relation with diagrammatic protocols. This work provides bridges between the new theory of planar para algebras and quantum information, especially in questions involving communication in quantum networks.
Intriguing Optoelectronic Properties of Metal Halide Perovskites.
Manser, Joseph S; Christians, Jeffrey A; Kamat, Prashant V
2016-11-09
A new chapter in the long and distinguished history of perovskites is being written with the breakthrough success of metal halide perovskites (MHPs) as solution-processed photovoltaic (PV) absorbers. The current surge in MHP research has largely arisen out of their rapid progress in PV devices; however, these materials are potentially suitable for a diverse array of optoelectronic applications. Like oxide perovskites, MHPs have ABX3 stoichiometry, where A and B are cations and X is a halide anion. Here, the underlying physical and photophysical properties of inorganic (A = inorganic) and hybrid organic-inorganic (A = organic) MHPs are reviewed with an eye toward their potential application in emerging optoelectronic technologies. Significant attention is given to the prototypical compound methylammonium lead iodide (CH3NH3PbI3) due to the preponderance of experimental and theoretical studies surrounding this material. We also discuss other salient MHP systems, including 2-dimensional compounds, where relevant. More specifically, this review is a critical account of the interrelation between MHP electronic structure, absorption, emission, carrier dynamics and transport, and other relevant photophysical processes that have propelled these materials to the forefront of modern optoelectronics research.
Exceptional Optoelectronic Properties of Hydrogenated Bilayer Silicene
Directory of Open Access Journals (Sweden)
Bing Huang
2014-05-01
Full Text Available Silicon is arguably the best electronic material, but it is not a good optoelectronic material. By employing first-principles calculations and the cluster-expansion approach, we discover that hydrogenated bilayer silicene (BS shows promising potential as a new kind of optoelectronic material. Most significantly, hydrogenation converts the intrinsic BS, a strongly indirect semiconductor, into a direct-gap semiconductor with a widely tunable band gap. At low hydrogen concentrations, four ground states of single- and double-sided hydrogenated BS are characterized by dipole-allowed direct (or quasidirect band gaps in the desirable range from 1 to 1.5 eV, suitable for solar applications. At high hydrogen concentrations, three well-ordered double-sided hydrogenated BS structures exhibit direct (or quasidirect band gaps in the color range of red, green, and blue, affording white light-emitting diodes. Our findings open opportunities to search for new silicon-based light-absorption and light-emitting materials for earth-abundant, high-efficiency, optoelectronic applications.
Quantum Transport and Optoelectronics in Gapped Graphene Nanodevices
2016-11-30
Performance 3. DATES COVERED (From - To) 01 Aug 2011 to 31 Jul 2016 4. TITLE AND SUBTITLE QUANTUM TRANSPORT AND OPTOELECTRONICS IN GAPPED GRAPHENE...nanodevices. To achieve this we will combine optoelectronic and plasmonic device structures with atomically seamless electrical contacts. The devices will...be based on fully band gap engineered bilayer graphene and graphene nanoribbons, resulting in all-carbon nanoelectronic devices with optoelectronic
Holographic fluorescence microscopy with incoherent digital holographic adaptive optics.
Jang, Changwon; Kim, Jonghyun; Clark, David C; Lee, Seungjae; Lee, Byoungho; Kim, Myung K
2015-01-01
Introduction of adaptive optics technology into astronomy and ophthalmology has made great contributions in these fields, allowing one to recover images blurred by atmospheric turbulence or aberrations of the eye. Similar adaptive optics improvement in microscopic imaging is also of interest to researchers using various techniques. Current technology of adaptive optics typically contains three key elements: a wavefront sensor, wavefront corrector, and controller. These hardware elements tend to be bulky, expensive, and limited in resolution, involving, for example, lenslet arrays for sensing or multiactuator deformable mirrors for correcting. We have previously introduced an alternate approach based on unique capabilities of digital holography, namely direct access to the phase profile of an optical field and the ability to numerically manipulate the phase profile. We have also demonstrated that direct access and compensation of the phase profile are possible not only with conventional coherent digital holography, but also with a new type of digital holography using incoherent light: selfinterference incoherent digital holography (SIDH). The SIDH generates a complex—i.e., amplitude plus phase—hologram from one or several interferograms acquired with incoherent light, such as LEDs, lamps, sunlight, or fluorescence. The complex point spread function can be measured using guide star illumination and it allows deterministic deconvolution of the full-field image. We present experimental demonstration of aberration compensation in holographic fluorescence microscopy using SIDH. Adaptive optics by SIDH provides new tools for improved cellular fluorescence microscopy through intact tissue layers or other types of aberrant media.
Universality of Holographic Phase Transitions and Holographic Quantum Liquids
Benincasa, Paolo
2009-01-01
We explore the phase structure for defect theories in full generality using the gauge/gravity correspondence. On the gravity side, the systems are constructed by introducing M (probe) D(p+4-2k)-branes in a background generated by N Dp-branes to obtain a codimension-k intersection. The dual gauge theory is a U(N) Supersymmetric Yang-Mills theory on a (1+p-k)-dimensional defect with both adjoint and fundamental degrees of freedom. We focus on the phase structure in the chemical potential versus temperature plane. We observe the existence of two universality classes for holographic gauge theories, which are identified by the order of the phase transition in the interior of the chemical potential/temperature plane. Specifically, all the sensible systems with no defect show a third order phase transition. Gauge theories on a defect with (p-1)-spatial directions are instead characterised by a second order phase transition. One can therefore state that the order of this phase transition is intimately related to the ...
Holographic fluorescence microscopy with incoherent digital holographic adaptive optics
Jang, Changwon; Kim, Jonghyun; Clark, David C.; Lee, Seungjae; Lee, Byoungho; Kim, Myung K.
2015-11-01
Introduction of adaptive optics technology into astronomy and ophthalmology has made great contributions in these fields, allowing one to recover images blurred by atmospheric turbulence or aberrations of the eye. Similar adaptive optics improvement in microscopic imaging is also of interest to researchers using various techniques. Current technology of adaptive optics typically contains three key elements: a wavefront sensor, wavefront corrector, and controller. These hardware elements tend to be bulky, expensive, and limited in resolution, involving, for example, lenslet arrays for sensing or multiactuator deformable mirrors for correcting. We have previously introduced an alternate approach based on unique capabilities of digital holography, namely direct access to the phase profile of an optical field and the ability to numerically manipulate the phase profile. We have also demonstrated that direct access and compensation of the phase profile are possible not only with conventional coherent digital holography, but also with a new type of digital holography using incoherent light: selfinterference incoherent digital holography (SIDH). The SIDH generates a complex-i.e., amplitude plus phase-hologram from one or several interferograms acquired with incoherent light, such as LEDs, lamps, sunlight, or fluorescence. The complex point spread function can be measured using guide star illumination and it allows deterministic deconvolution of the full-field image. We present experimental demonstration of aberration compensation in holographic fluorescence microscopy using SIDH. Adaptive optics by SIDH provides new tools for improved cellular fluorescence microscopy through intact tissue layers or other types of aberrant media.
Focused Ion Beam Technology for Optoelectronic Devices
Reithmaier, J. P.; Bach, L.; Forchel, A.
2003-08-01
High-resolution proximity free lithography was developed using InP as anorganic resist for ion beam exposure. InP is very sensitive on ion beam irradiation and show a highly nonlinear dose dependence with a contrast function comparable to organic electron beam resists. In combination with implantation induced quantum well intermixing this new lithographic technique based on focused ion beams is used to realize high performance nano patterned optoelectronic devices like complex coupled distributed feedback (DFB) and distributed Bragg reflector (DBR) lasers.
Graphene optoelectronics synthesis, characterization, properties, and applications
bin M Yusoff, Abdul Rashid
2014-01-01
This first book on emerging applications for this innovative material gives an up-to-date account of the many opportunities graphene offers high-end optoelectronics.The text focuses on potential as well as already realized applications, discussing metallic and passive components, such as transparent conductors and smart windows, as well as high-frequency devices, spintronics, photonics, and terahertz devices. Also included are sections on the fundamental properties, synthesis, and characterization of graphene. With its unique coverage, this book will be welcomed by materials scientists, solid-
Organic ferroelectric opto-electronic memories
Directory of Open Access Journals (Sweden)
Kamal Asadi
2011-12-01
Full Text Available Memory is a prerequisite for many electronic devices. Organic non-volatile memory devices based on ferroelectricity are a promising approach towards the development of a low-cost memory technology based on a simple cross-bar array. In this review article we discuss the latest developments in this area with a focus on the most promising opto-electronic device concept, i.e., bistable rectifying diodes. The integration of these diodes into larger memory arrays is discussed. Through a clever design of the electrodes we demonstrate light emitting diodes with integrated built-in switches that can be applied in signage applications.
Statistical conjugated polymers comprising optoelectronically distinct units.
Hollinger, Jon; Sun, Jing; Gao, Dong; Karl, Dominik; Seferos, Dwight S
2013-03-12
Poly(3-heptylselenophene)-stat-poly(3-hexylthiophene) is synthesized and characterized in terms of its crystallinity and performance in an organic photovoltaic (OPV) cell. Despite the random distribution of units along the polymer main chain, the material is semi-crystalline, as demonstrated by differential scanning calorimetry and wide-angle X-ray diffraction. Thin-film absorption suggests an increased compatibility than seen with 3-hexylselenophene monomer. Optoelectronic properties are an average of the two homopolymers, and OPV performance is enhanced by a broadened absorption profile and a favorable morphology.
System of Optoelectronic Sensors for Breath Analysis
Directory of Open Access Journals (Sweden)
Mikołajczyk Janusz
2016-09-01
Full Text Available The paper describes an integrated laser absorption system as a potential tool for breath analysis for clinical diagnostics, online therapy monitoring and metabolic disorder control. The sensors operate basing on cavity enhanced spectroscopy and multi-pass spectroscopy supported by wavelength modulation spectroscopy. The aspects concerning selection of operational spectral range and minimization of interference are also discussed. Tests results of the constructed devices collected with reference samples of biomarkers are also presented. The obtained data provide an opportunity to analyse applicability of optoelectronic sensors in medical screening.
In-situ nanochemistry for optoelectronics
Kim, Won Jin
This thesis describes recent results on simple methods to arrange nanosize objects such as semiconductor nanocrystals, noble metal nanoparticles, and upconversion nanophosphors by means of top-down processes. Specific focus is directed towards approaches to produce predefined patterns of various nanostructure materials using optical lithography for direct writing of films for optoelectronic and electronic devices. To obtain photo-patternability, the nanostructure materials [for example semiconductor nanocrystals (CdSe, CdTe, PbSe), metallic nanoparticles (Ag), upconversion nanophosphors (Er3+/Yb 3+ or Tm3+/Yb3+ co-doped NaYF4 ), and transparent conducting oxide nanoparticles (ITO, ZnO)] were functionalized by incorporation of the functional ligand t-butoxycarbonyl (t-BOC) which has an acid-labile moiety. The t-BOC group undergoes a cleavage, when subjected to UV irradiation in the presence of a photo acid generator (PAG) to releases isobutene and carbon dioxide. Depending on the need of the application, either the exposed regions (negative pattern) or the non-exposed regions (positive pattern) could be developed from the exposed films by appropriate solvent selection. The photo exposed regions of the film are rendered hydrophilic due to the degradation of the t-BOC, the un-exposed regions remain hydrophobic. This solubility change in the QDs is the basis of their patternablity. The un-exposed regions can be removed to obtain the negative pattern by washing with hydrophobic solvents, whereas the exposed regions can be selectively removed to obtain positive pattern by washing with hydrophilic solvents. This change in the surface chemistry results in the ability to photo-pattern the various nanostructure materials where desired for a number of optoelectronic device geometries. We demonstrate that the ultimate resolution (linewidth and spacing) of this technique is below submicron. Details on technological aspects concerning nanoparticle patterning as well as practical
Monolithically integrated optoelectronic down-converter (MIOD)
Portnoi, Efrim L.; Venus, G. B.; Khazan, A. A.; Gorfinkel, Vera B.; Kompa, Guenter; Avrutin, Evgenii A.; Thayne, Iain G.; Barrow, David A.; Marsh, John H.
1995-06-01
Optoelectronic down-conversion of very high-frequency amplitude-modulated signals using a semiconductor laser simultaneously as a local oscillator and a mixer is proposed. Three possible constructions of a monolithically integrated down-converter are considered theoretically: a four-terminal semiconductor laser with dual pumping current/modal gain control, and both a passively mode-locked and a passively Q-switched semiconductor laser monolithically integrated with an electroabsorption or pumping current modulator. Experimental verification of the feasibility of the concept of down conversion in a laser diode is presented.
Coherent optoelectronics with single quantum dots
Energy Technology Data Exchange (ETDEWEB)
Zrenner, A; Ester, P; Michaelis de Vasconcellos, S; Huebner, M C; Lackmann, L; Stufler, S [Universitaet Paderborn, Department Physik, Warburger Strasse 100, D-33098 Paderborn (Germany); Bichler, M [Walter Schottky Institut, Technische Universitaet Muenchen, Am Coulombwall, D-85748 Garching (Germany)], E-mail: zrenner@mail.upb.de
2008-11-12
The optical properties of semiconductor quantum dots are in many respects similar to those of atoms. Since quantum dots can be defined by state-of-the-art semiconductor technologies, they exhibit long-term stability and allow for well-controlled and efficient interactions with both optical and electrical fields. Resonant ps excitation of single quantum dot photodiodes leads to new classes of coherent optoelectronic functions and devices, which exhibit precise state preparation, phase-sensitive optical manipulations and the control of quantum states by electrical fields.
Coherent optoelectronics with single quantum dots
Zrenner, A.; Ester, P.; Michaelis de Vasconcellos, S.; Hübner, M. C.; Lackmann, L.; Stufler, S.; Bichler, M.
2008-11-01
The optical properties of semiconductor quantum dots are in many respects similar to those of atoms. Since quantum dots can be defined by state-of-the-art semiconductor technologies, they exhibit long-term stability and allow for well-controlled and efficient interactions with both optical and electrical fields. Resonant ps excitation of single quantum dot photodiodes leads to new classes of coherent optoelectronic functions and devices, which exhibit precise state preparation, phase-sensitive optical manipulations and the control of quantum states by electrical fields.
Directory of Open Access Journals (Sweden)
N.S. Mazhari
2017-03-01
Full Text Available The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution, a solution with cylindrical symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not have any such dependence.
Mazhari, N S; Bahamonde, Sebastian; Faizal, Mir; Myrzakulov, Ratbay
2016-01-01
The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution and a solution with cylindrically symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not any such dependence.
On effective holographic Mott insulators
Baggioli, Matteo; Pujolàs, Oriol
2016-12-01
We present a class of holographic models that behave effectively as prototypes of Mott insulators — materials where electron-electron interactions dominate transport phenomena. The main ingredient in the gravity dual is that the gauge-field dynamics contains self-interactions by way of a particular type of non-linear electrodynamics. The electrical response in these models exhibits typical features of Mott-like states: i) the low-temperature DC conductivity is unboundedly low; ii) metal-insulator transitions appear by varying various parameters; iii) for large enough self-interaction strength, the conductivity can even decrease with increasing doping (density of carriers) — which appears as a sharp manifestation of `traffic-jam'-like behaviour; iv) the insulating state becomes very unstable towards superconductivity at large enough doping. We exhibit some of the properties of the resulting insulator-superconductor transition, which is sensitive to the momentum dissipation rate in a specific way. These models imply a clear and generic correlation between Mott behaviour and significant effects in the nonlinear electrical response. We compute the nonlinear current-voltage curve in our model and find that indeed at large voltage the conductivity is largely reduced.
Holographic Entropy and Calabi's Diastasis
D'Hoker, Eric
2014-01-01
The entanglement entropy for interfaces and junctions of two-dimensional CFTs is evaluated on holographically dual half-BPS solutions to six-dimensional Type 4b supergravity with m anti-symmetric tensor supermultiplets. It is shown that the moduli space for an N-junction solution projects to N points in the Kaehler manifold SO(2,m)/( SO(2) x SO(m)). For N=2 the interface entropy is expressed in terms of the central charge and Calabi's diastasis function on SO(2,m)/(SO(2) x SO(m)), thereby lending support from holography to a proposal of Bachas, Brunner, Douglas, and Rastelli. For N=3, the entanglement entropy for a 3-junction decomposes into a sum of diastasis functions between pairs, weighed by combinations of the three central charges, provided the flux charges are all parallel to one another or, more generally, provided the space of flux charges is orthogonal to the space of unattracted scalars. Under similar assumptions for N>3, the entanglement entropy for the N-junction solves a variational problem whos...
A Holographic Quantum Hall Ferromagnet
Kristjansen, C; Semenoff, G W
2013-01-01
A detailed numerical study of a recent proposal for exotic states of the D3-probe D5 brane system with charge density and an external magnetic field is presented. The state has a large number of coincident D5 branes blowing up to a D7 brane in the presence of the worldvolume electric and magnetic fields which are necessary to construct the holographic state. Numerical solutions have shown that these states can compete with the the previously known chiral symmetry breaking and maximally symmetric phases of the D3-D5 system. Moreover, at integer filling fractions, they are incompressible with integer quantized Hall conductivities. In the dual superconformal defect field theory, these solutions correspond to states which break the chiral and global flavor symmetries spontaneously. The region of the temperature-density plane where the D7 brane has lower energy than the other known D5 brane solutions is identified. A hypothesis for the structure of states with filling fraction and Hall conductivity greater than on...
Holographic confinement in inhomogeneous backgrounds
Marolf, Donald; Wien, Jason
2016-08-01
As noted by Witten, compactifying a d-dimensional holographic CFT on an S 1 gives a class of ( d - 1)-dimensional confining theories with gravity duals. The proto-typical bulk solution dual to the ground state is a double Wick rotation of the AdS d+1 Schwarzschild black hole known as the AdS soliton. We generalize such examples by allowing slow variations in the size of the S 1, and thus in the confinement scale. Coefficients governing the second order response of the system are computed for 3 ≤ d ≤ 8 using a derivative expansion closely related to the fluid-gravity correspondence. The primary physical results are that i) gauge-theory flux tubes tend to align orthogonal to gradients and along the eigenvector of the Hessian with the lowest eigenvalue, ii) flux tubes aligned orthogonal to gradients are attracted to gradients for d ≤ 6 but repelled by gradients for d ≥ 7, iii) flux tubes are repelled by regions where the second derivative along the tube is large and positive but are attracted to regions where the eigenvalues of the Hessian are large and positive in directions orthogonal to the tube, and iv) for d > 3, inhomogeneities act to raise the total energy of the confining vacuum above its zeroth order value.
Holographic confinement in inhomogenous backgrounds
Marolf, Donald
2016-01-01
As noted by Witten, compactifying a $d$-dimensional holographic CFT on an $S^1$ gives a class of $(d-1)$-dimensional confining theories with gravity duals. The prototypical bulk solution dual to the ground state is a double Wick rotation of the AdS$_{d+1}$ Schwarzschild black hole known as the AdS soliton. We generalize such examples by allowing slow variations in the size of the $S^1$, and thus in the confinement scale. Coefficients governing the second order response of the system are computed for $3 \\le d \\le 8$ using a derivative expansion closely related to the fluid-gravity correspondence. The primary physical results are that i) gauge-theory flux tubes tend to align orthogonal to gradients and along the eigenvector of the Hessian with the lowest eigenvalue, ii) flux tubes aligned orthogonal to gradients are attracted to gradients for $d \\le 6$ but repelled by gradients for $d \\ge 7$, iii) flux tubes are repelled by regions where the second derivative along the tube is large and positive but are attract...
Holographic quenches and anomalous transport
Ammon, Martin; Grieninger, Sebastian; Jimenez-Alba, Amadeo; Macedo, Rodrigo P.; Melgar, Luis
2016-09-01
We study the response of the chiral magnetic effect due to continuous quenches induced by time dependent electric fields within holography. Concretely, we consider a holographic model with dual chiral anomaly and compute the electric current parallel to a constant, homogeneous magnetic field and a time dependent electric field in the probe approximation. We explicitly solve the PDEs by means of pseudospectral methods in spatial and time directions and study the transition to an universal "fast" quench response. Moreover, we compute the amplitudes, i.e., residues of the quasi normal modes, by solving the (ODE) Laplace transformed equations. We investigate the possibility of considering the asymptotic growth rate of the amplitudes as a well defined notion of initial time scale for linearized systems. Finally, we highlight the existence of Landau level resonances in the electrical conductivity parallel to a magnetic field at finite frequency and show explicitly that these only appear in presence of the anomaly. We show that the existence of these resonances induces, among others, a long-lived AC electric current once the electric field is switched off.
Linearity of Holographic Entanglement Entropy
Almheiri, Ahmed; Swingle, Brian
2016-01-01
We consider the question of whether the leading contribution to the entanglement entropy in holographic CFTs is truly given by the expectation value of a linear operator as is suggested by the Ryu-Takayanagi formula. We investigate this property by computing the entanglement entropy, via the replica trick, in states dual to superpositions of macroscopically distinct geometries and find it consistent with evaluating the expectation value of the area operator within such states. However, we find that this fails once the number of semi-classical states in the superposition grows exponentially in the central charge of the CFT. Moreover, in certain such scenarios we find that the choice of surface on which to evaluate the area operator depends on the density matrix of the entire CFT. This nonlinearity is enforced in the bulk via the homology prescription of Ryu-Takayanagi. We thus conclude that the homology constraint is not a linear property in the CFT. We also discuss the existence of entropy operators in genera...
Theta dependence in Holographic QCD
Bartolini, Lorenzo; Bolognesi, Stefano; Cotrone, Aldo L; Manenti, Andrea
2016-01-01
We study the effects of the CP-breaking topological $\\theta$-term in the large $N_c$ QCD model by Witten, Sakai and Sugimoto with $N_f$ degenerate light flavors. We first compute the ground state energy density, the topological susceptibility and the masses of the lowest lying mesons, finding agreement with expectations from the QCD chiral effective action. Then, focusing on the $N_f=2$ case, we consider the baryonic sector and determine, to leading order in the small $\\theta$ regime, the related holographic instantonic soliton solutions. We find that while the baryon spectrum does not receive ${\\cal O}(\\theta)$ corrections, this is not the case for observables like the electromagnetic form factor of the nucleons. In particular, it exhibits a dipole term, which turns out to be vector-meson dominated. The resulting neutron electric dipole moment, which is exactly the opposite as that of the proton, is of the same order of magnitude of previous estimates in the literature. Finally, we compute the CP-violating p...
Towards Unquenched Holographic Magnetic Catalysis
Filev, Veselin G
2011-01-01
We propose a string dual to the SU(Nc) N=4 SYM coupled to Nf massless fundamental flavors in an external magnetic field. The flavors are introduced by homogeneously smeared Nf D7-branes and the external magnetic field via a non-trivial Kalb-Rammond B-field. Our solution is perturbative in a parameter that counts the number of internal flavor loops. In the limit of vanishing B-field the background reduces to the supersymmetric one obtained in hep-th/0612118. We introduce an additional probe D7--brane and in the supersymmetric limit of vanishing B-field perform a holographic renormalization of its "on-shell" action. We consider also non-supersymmetric probes with fixed worldvolume gauge field corresponding to a magnetic field coupled only to the fundamental fields of the probe brane. We study the influence of the backreacted flavors on the effect of dynamical mass generation. Qualitatively the physical picture remains unchanged. In the next step we consider the case when the magnetic field couples to both the b...
Collapse and Revival in Holographic Quenches
da Silva, Emilia; Mas, Javier; Serantes, Alexandre
2014-01-01
We study holographic models related to global quantum quenches in finite size systems. The holographic set up describes naturally a CFT, which we consider on a circle and a sphere. The enhanced symmetry of the conformal group on the circle motivates us to compare the evolution in both cases. Depending on the initial conditions, the dual geometry exhibits oscillations that we holographically interpret as revivals of the initial field theory state. On the sphere, this only happens when the energy density created by the quench is small compared to the system size. However on the circle considerably larger energy densities are compatible with revivals. Two different timescales emerge in this latter case. A collapse time, when the system appears to have dephased, and the revival time, when after rephasing the initial state is partially recovered. The ratio of these two times depends upon the initial conditions in a similar way to what is observed in some experimental setups exhibiting collapse and revivals.
Phases of kinky holographic nuclear matter
Elliot-Ripley, Matthew; Zamaklar, Marija
2016-01-01
Holographic QCD at finite baryon number density and zero temperature is studied within the five-dimensional Sakai-Sugimoto model. We introduce a new approximation that models a smeared crystal of solitonic baryons by assuming spatial homogeneity to obtain an effective kink theory in the holographic direction. The kink theory correctly reproduces a first order phase transition to lightly bound nuclear matter. As the density is further increased the kink splits into a pair of half-kink constituents, providing a concrete realization of the previously suggested dyonic salt phase, where the bulk soliton splits into constituents at high density. The kink model also captures the phenomenon of baryonic popcorn, in which a first order phase transition generates an additional soliton layer in the holographic direction. We find that this popcorn transition takes place at a density below the dyonic salt phase, making the latter energetically unfavourable. However, the kink model predicts only one pop, rather than the seq...
Holographic duality in condensed matter physics
Zaanen, Jan; Sun, Ya-Wen; Schalm, Koenraad
2015-01-01
A pioneering treatise presenting how the new mathematical techniques of holographic duality unify seemingly unrelated fields of physics. This innovative development morphs quantum field theory, general relativity and the renormalisation group into a single computational framework and this book is the first to bring together a wide range of research in this rapidly developing field. Set within the context of condensed matter physics and using boxes highlighting the specific techniques required, it examines the holographic description of thermal properties of matter, Fermi liquids and superconductors, and hitherto unknown forms of macroscopically entangled quantum matter in terms of general relativity, stars and black holes. Showing that holographic duality can succeed where classic mathematical approaches fail, this text provides a thorough overview of this major breakthrough at the heart of modern physics. The inclusion of extensive introductory material using non-technical language and online Mathematica not...
Holographic Butterfly Effect at Quantum Critical Points
Ling, Yi; Wu, Jian-Pin
2016-01-01
When the Lyapunov exponent $\\lambda_L$ in a quantum chaotic system saturates the bound $\\lambda_L\\leqslant 2\\pi k_BT$, it is proposed that this system has a holographic dual described by a gravity theory. In particular, the butterfly effect as a prominent phenomenon of chaos can ubiquitously exist in a black hole system characterized by a shockwave solution near the horizon. In this letter we propose that the butterfly velocity $v_B$ can be used to diagnose quantum phase transition (QPT) in holographic theories. We provide evidences for this proposal with two holographic models exhibiting metal-insulator transitions (MIT), in which the second derivative of $v_B$ with respect to system parameters characterizes quantum critical points (QCP) with local extremes. We also point out that this proposal can be tested by experiments in the light of recent progress on the measurement of out-of-time-order correlation function (OTOC).
Collapse and revival in holographic quenches
da Silva, Emilia; Lopez, Esperanza; Mas, Javier; Serantes, Alexandre
2015-04-01
We study holographic models related to global quantum quenches in finite size systems. The holographic set up describes naturally a CFT, which we consider on a circle and a sphere. The enhanced symmetry of the conformal group on the circle motivates us to compare the evolution in both cases. Depending on the initial conditions, the dual geometry exhibits oscillations that we holographically interpret as revivals of the initial field theory state. On the sphere, this only happens when the energy density created by the quench is small compared to the system size. However on the circle considerably larger energy densities are compatible with revivals. Two different timescales emerge in this latter case. A collapse time, when the system appears to have dephased, and the revival time, when after rephasing the initial state is partially recovered. The ratio of these two times depends upon the initial conditions in a similar way to what is observed in some experimental setups exhibiting collapse and revivals.
The holographic Weyl semi-metal
Directory of Open Access Journals (Sweden)
Karl Landsteiner
2016-02-01
Full Text Available We present a holographic model of a Weyl semi-metal. We show the evidences that upon varying a mass parameter the model undergoes a sharp crossover at small temperature from a topologically non-trivial state to a trivial one. The order parameter is the anomalous Hall effect (AHE and we find that it is very strongly suppressed above a critical value of the mass parameter. This can be taken as a hint for an underlying topological quantum phase transition. We give an interpretation of the results in terms of a holographic RG flow and compare to a weakly coupled field theoretical model. Since there are no fermionic quasiparticle excitations in the strongly coupled holographic model the presence of an anomalous Hall effect cannot be bound to notions of topology in momentum spaces.
Fidelity Susceptibility as Holographic PV criticality
Momeni, Davood; Myrzakulov, Ratbay
2016-01-01
Motivated by the fact that the quantum entanglement entropy is dual to an area in AdS, quantities dual to a volume in the AdS have also been recently proposed. These include the holographic complexity and fidelity susceptibility of a quantum system. Even though both of them are dual to an volume in the bulk, there are some interesting difference between them. In this letter, we will explicitly compare them for an $ AdS _4$ solution, and clarify the main differences between them from thermodynamic point of the view. We will also obtain the correct and appropriate holographic dual of the thermodynamic volume of AdS blackhole, and demonstrate that to explain therodynamic in extended phase PV picture, from the AdS/CFT point of view,fidelity susceptibility is the preferred quantity in comparison to holographic complexity.
Liquid crystals for holographic optical data storage
DEFF Research Database (Denmark)
Matharu, Avtar; Jeeva, S.; Ramanujam, P.S.
2007-01-01
A tutorial review is presented to inform and inspire the reader to develop and integrate strong scientific links between liquid crystals and holographic data storage, from a materials scientist's viewpoint. The principle of holographic data storage as a means of providing a solution...... to the information storage demands of the 21st century is detailed. Holography is a small subset of the much larger field of optical data storage and similarly, the diversity of materials used for optical data storage is enormous. The theory of polarisation holography which produces holograms of constant intensity......, is discussed. Polymeric liquid crystals play an important role in the development of materials for holographic storage and photoresponsive materials based on azobenzene are targeted for discussion due to their ease of photo- reversion between trans- and cis- states. Although the final polymer may not be liquid...
The holographic Weyl semi-metal
Energy Technology Data Exchange (ETDEWEB)
Landsteiner, Karl, E-mail: karl.landsteiner@csic.es; Liu, Yan, E-mail: yan.liu@csic.es
2016-02-10
We present a holographic model of a Weyl semi-metal. We show the evidences that upon varying a mass parameter the model undergoes a sharp crossover at small temperature from a topologically non-trivial state to a trivial one. The order parameter is the anomalous Hall effect (AHE) and we find that it is very strongly suppressed above a critical value of the mass parameter. This can be taken as a hint for an underlying topological quantum phase transition. We give an interpretation of the results in terms of a holographic RG flow and compare to a weakly coupled field theoretical model. Since there are no fermionic quasiparticle excitations in the strongly coupled holographic model the presence of an anomalous Hall effect cannot be bound to notions of topology in momentum spaces.
Holographic dark energy in the DGP model
Energy Technology Data Exchange (ETDEWEB)
Cruz, Norman [Universidad de Santiago, Departamento de Fisica, Facultad de Ciencia, Santiago (Chile); Lepe, Samuel [Pontificia Universidad Catolica de Valparaiso, Instituto de Fisica, Facultad de Ciencias, Valparaiso (Chile); Pena, Francisco [Universidad de La Frontera, Departamento de Ciencias Fisicas, Facultad de Ingenieria, Ciencias y Administracion, Avda. Francisco Salazar 01145, Casilla 54-D, Temuco (Chile); Avelino, Arturo [Universidad de Guanajuato, Departamento de Fisica, DCI, Codigo Postal 37150, Leon, Guanajuato (Mexico)
2012-09-15
The braneworld model proposed by Dvali, Gabadadze, and Porrati leads to an accelerated universe without cosmological constant or any other form of dark energy. Nevertheless, we have investigated the consequences of this model when an holographic dark energy is included, taking the Hubble scale as IR cutoff. We have found that the holographic dark energy leads to an accelerated flat universe (de Sitter-like expansion) for the two branches: {epsilon}={+-}1, of the DGP model. Nevertheless, in universes with no null curvature the dark energy presents an EoS corresponding to a phantom fluid during the present era and evolving to a de Sitter-like phase for future cosmic time. In the special case in which the holographic parameter c is equal to one we have found a sudden singularity in closed universes. In this case the expansion is decelerating. (orig.)
Holographic bulk viscosity: GPR vs EO
Buchel, Alex; Kiritsis, Elias
2011-01-01
Recently Eling and Oz (EO) proposed a formula for the holographic bulk viscosity, in arXiv:1103.1657, derived from the null horizon focusing equation. This formula seems different from that obtained earlier by Gubser, Pufu and Rocha (GPR) in arXiv:0806.0407 calculated from the IR limit of the two-point function of the trace of the stress tensor. The two were shown to agree only for some simple scaling cases. We point out that the two formulae agree in two non-trivial holographic theories describing RG flows. The first is the strongly coupled N=2* gauge theory plasma. The second is the semi-phenomenological model of Improved Holographic QCD.
A holographic model for black hole complementarity
Lowe, David A
2016-01-01
In the version of black hole complementarity advocated by the authors, interior infalling degrees of freedom evolve according to the usual semiclassical effective field theory, generating the black hole interior via propagation along geodesics. Meanwhile the exterior degrees of freedom evolve according to an exact description of holographic origin. The infalling degrees of freedom have a complementary description in terms of outgoing Hawking radiation and must eventually decohere with respect to the exterior Hamiltonian, leading to apparent violations of quantum mechanics for an infaller. Trace distance is used to quantify the difference between these complementary time evolutions, and to define the decoherence time and the scrambling time. In a particular model for the holographic theory which exhibits fast scrambling, we show these timescales coincide. Moreover we propose a dictionary between the holographic theory and the bulk description where mean field evolution corresponds to the evolution with respect...
Anomalous transport and holographic momentum relaxation
Copetti, Christian; Fernández-Pendás, Jorge; Landsteiner, Karl; Megías, Eugenio
2017-09-01
The chiral magnetic and vortical effects denote the generation of dissipationless currents due to magnetic fields or rotation. They can be studied in holographic models with Chern-Simons couplings dual to anomalies in field theory. We study a holographic model with translation symmetry breaking based on linear massless scalar field backgrounds. We compute the electric DC conductivity and find that it can vanish for certain values of the translation symmetry breaking couplings. Then we compute the chiral magnetic and chiral vortical conductivities. They are completely independent of the holographic disorder couplings and take the usual values in terms of chemical potential and temperature. To arrive at this result we suggest a new definition of energy-momentum tensor in presence of the gravitational Chern-Simons coupling.
Colloidal quantum dots as optoelectronic elements
Vasudev, Milana; Yamanaka, Takayuki; Sun, Ke; Li, Yang; Yang, Jianyong; Ramadurai, Dinakar; Stroscio, Michael A.; Dutta, Mitra
2007-02-01
Novel optoelectronic systems based on ensembles of semiconductor nanocrystals are addressed in this paper. Colloidal semiconductor quantum dots and related quantum-wire structures have been characterized optically; these optical measurements include those made on self-assembled monolayers of DNA molecules terminated on one end with a common substrate and on the other end with TiO II quantum dots. The electronic properties of these structures are modeled and compared with experiment. The characterization and application of ensembles of colloidal quantum dots with molecular interconnects are considered. The chemically-directed assembly of ensembles of colloidal quantum dots with biomolecular interconnects is demonstrated with quantum dot densities in excess of 10 +17 cm -3. A number of novel photodetectors have been designed based on the combined use of double-barrier quantum-well injectors, colloidal quantum dots, and conductive polymers. Optoelectronic devices including photodetectors and solar cells based on threedimensional ensembles of quantum dots are considered along with underlying phenomena such as miniband formation and the robustness of minibands to displacements of quantum dots in the ensemble.
Pole movement in electronic and optoelectronic oscillators
Chatterjee, S.; Pal, S.; Biswas, B. N.
2013-12-01
An RLC circuit with poles on the left half of the complex frequency plane is capable of executing transient oscillations. During this period, energy conversion from potential to kinetic and from kinetic to potential continuously goes on, until the stored energy is lost in dissipation through the resistance. On the other hand, in an electronic or opto-electronic oscillator with an embedded RLC circuit, the poles are forcibly placed on the right-half plane (RHP) and as far as practicable away from the imaginary axis in order to help the growth of oscillation as quickly as possible. And ultimately, it is imagined that, like the case of an ideal linear harmonic oscillator, the poles are frozen on the imaginary axis so that the oscillation neither grows nor decays. The authors feel that this act of holding the poles right on the imaginary axis is a theoretical conjecture in a soft or hard self-excited oscillator. In this article, a detailed discussion on pole movement in an electronic and opto-electronic oscillator is carried out from the basic concept. A new analytical method for estimating the time-dependent part of the pole is introduced here.
Reconfigurable Optical Interconnections Using Dynamic Optoelectronic Holograms
Schulze, Elmar
1988-04-01
Increasing complexity and processing speed of electronic circuits and a high device density have led to serious problems in electrical interconnections. Their limitations arise from their signal transmission capacity. power consumption. crosstalk. and reliability. Optical links may solve such problems by offering high data rates of several gigabits per second. large fanouts of up to 100 loads. good reliability and less power expenditure. Optical fibers, integrated optical waveguides or free-space transmission links may be applicable. For the free-space links, lenses. mirrors and holograms can be used to guide the light waves. In this paper, reconfigurable optical interconnection schemes are proposed and described which are based on optoelectronic holograms. Their interference patterns can be changed dynamically. To establish connections as free-space links, the light beams emitted from even hundreds of light sources are imaged onto an array of small dynamic holograms. Their interference patterns are optically and electronically controllable. These holograms diffract and focus each of the incident light beams individually onto the receiving photo-diodes. By changing the hologram interference patterns dynamically. an optical switch is obtained. It renders the establishment of reconfigurable optical interconnections. As optoelectronic holograms very-high-resolution spatial light modulators are proposed.
Optoelectronic pH Meter: Further Details
Jeevarajan, Antony S.; Anderson, Mejody M.; Macatangay, Ariel V.
2009-01-01
A collection of documents provides further detailed information about an optoelectronic instrument that measures the pH of an aqueous cell-culture medium to within 0.1 unit in the range from 6.5 to 7.5. The instrument at an earlier stage of development was reported in Optoelectronic Instrument Monitors pH in a Culture Medium (MSC-23107), NASA Tech Briefs, Vol. 28, No. 9 (September 2004), page 4a. To recapitulate: The instrument includes a quartz cuvette through which the medium flows as it is circulated through a bioreactor. The medium contains some phenol red, which is an organic pH-indicator dye. The cuvette sits between a light source and a photodetector. [The light source in the earlier version comprised red (625 nm) and green (558 nm) light-emitting diodes (LEDs); the light source in the present version comprises a single green- (560 nm)-or-red (623 nm) LED.] The red and green are repeatedly flashed in alternation. The responses of the photodiode to the green and red are processed electronically to obtain the ratio between the amounts of green and red light transmitted through the medium. The optical absorbance of the phenol red in the green light varies as a known function of pH. Hence, the pH of the medium can be calculated from the aforesaid ratio.
Holographic RG flows with nematic IR phases
Cremonini, Sera; Rong, Junchen; Sun, Kai
2014-01-01
We construct zero-temperature geometries that interpolate between a Lifshitz fixed point in the UV and an IR phase that breaks spatial rotations but preserves translations. We work with a simple holographic model describing two massive gauge fields coupled to gravity and a neutral scalar. Our construction can be used to describe RG flows in non-relativistic, strongly coupled quantum systems with nematic order in the IR. In particular, when the dynamical critical exponent of the UV fixed point is z=2 and the IR scaling exponents are chosen appropriately, our model realizes holographically the scaling properties of the bosonic modes of the quadratic band crossing model.
Top-down Holographic Glueball Decay Rates
Brünner, F; Rebhan, A
2015-01-01
We present new results on the decay patterns of scalar and tensor glueballs in the top-down holographic Witten-Sakai-Sugimoto model. This model, which has only one free dimensionless parameter, gives semi-quantitative predictions for the vector meson spectrum, their decay widths, and also a gluon condensate in agreement with SVZ sum rules. The holographic predictions for scalar glueball decay rates are compared with experimental data for the widely discussed gluon candidates f0(1500) and f0(1710).
Digital holographic Michelson interferometer for nanometrology
Sevrygin, Alexander A.; Korotkov, V. I.; Pulkin, S. A.; Tursunov, I. M.; Venediktov, D. V.; Venediktov, V. Yu.; Volkov, O. V.
2014-11-01
The paper considers the dynamic holographic interferometry schemes with amplification (multiplication) of holographic fringes and with correction for distortions, imposed by the interferometer scheme elements. The use of digital microscope and of the matrix light modulator with direct addressing provides the completely digital closed-loop performance of the overall system for real-time evaluation of nano-scale objects size. Considered schemes were verified in the laboratory experiment, using the Michelson micro-interferometer, equipped by the USB-microscope and digital holography stage, equipped by the Holoeye spatial light modulator.
Holographic corrections to meson scattering amplitudes
Energy Technology Data Exchange (ETDEWEB)
Armoni, Adi; Ireson, Edwin, E-mail: 746616@swansea.ac.uk
2017-06-15
We compute meson scattering amplitudes using the holographic duality between confining gauge theories and string theory, in order to consider holographic corrections to the Veneziano amplitude and associated higher-point functions. The generic nature of such computations is explained, thanks to the well-understood nature of confining string backgrounds, and two different examples of the calculation in given backgrounds are used to illustrate the details. The effect we discover, whilst only qualitative, is re-obtainable in many such examples, in four-point but also higher point amplitudes.
Holographic Corrections to Meson Scattering Amplitudes
Armoni, Adi
2016-01-01
We compute meson scattering amplitudes using the holographic duality between confining gauge theories and string theory, in order to consider holographic corrections to the Veneziano amplitude and associated higher-point functions. The generic nature of such computations is explained, thanks to the well-understood nature of confining string backgrounds, and two different examples of the calculation in given backgrounds are used to illustrate the details. The effect we discover, whilst only qualitative, is re-obtainable in many such examples, in four-point but also higher point amplitudes.
Order parameter fluctuations in the holographic superconductor
Plantz, N W M; Vandoren, S
2015-01-01
We investigate the effect of order parameter fluctuations in the holographic superconductor. In particular, the fully backreacted spectral functions of the order parameter in both the normal and the superconducting phase are computed. We also present a vector-like large-$N$ version of the Ginzburg-Landau model that accurately describes our long-wavelength results in both phases. The large-$N$ limit of the latter model explains why the Higgs mode and the second-sound mode are not present in the spectral functions. Our results indicate that the holographic superconductor describes a relativistic multi-component superfluid in the universal regime of the BEC-BCS crossover.
Sangac interferometer on the holographic bragg grating
Tikhonov, E A
2015-01-01
The ring interferometer with zero optical path difference known as Sagnac one is offered with a diffraction splitting of the entering light beam. As the beamsplitter, a transmission holographic Bragg grating is used. Conditions of normal operation of this interferometer achieve under the equal intensity of beam copies and the adjustable phase shift between them in its two interferometer shoulders. These conditions are met with the holographic grating, which provides the phase shift 180^0 on the central Bragg wavelength. Experimental approbation of the modified interferometer validates the expected results.
Holographic Aspects of a Relativistic Nonconformal Theory
Directory of Open Access Journals (Sweden)
Chanyong Park
2013-01-01
Full Text Available We study a general D-dimensional Schwarzschild-type black brane solution of the Einstein-dilaton theory and derive, by using the holographic renormalization, its thermodynamics consistent with the geometric results. Using the membrane paradigm, we calculate the several hydrodynamic transport coefficients and compare them with the results obtained by the Kubo formula, which shows the self-consistency of the gauge/gravity duality in the relativistic nonconformal theory. In order to understand more about the relativistic non-conformal theory, we further investigate the binding energy, drag force, and holographic entanglement entropy of the relativistic non-conformal theory.
On the Holographic Nature Of Rindler Energy
Halyo, Edi
2014-01-01
We show that the dimensionless Rindler energy of a black hole, $E_R$, is exactly the surface Hamiltonian obtained from the Einstein--Hilbert action evaluated on the horizon. Therefore, $E_R$ is given by a surface integral over the horizon and manifestly holographic. In the context of the AdS/CFT duality, Rindler energy corresponds, on the boundary, to a dimensionless energy given by the product of the AdS radius and the extensive part of the CFT energy. We find that, beyond General Relativity, $E_R$ is still holographic but not necessarily given by the surface Hamiltonian of the theory.
Riboflavin Sensitized Photopolymer Materials for Holographic Storage
Institute of Scientific and Technical Information of China (English)
ZHAI Feng-Xiao; WANG Ai-Rong; YIN Qiong; LIU Jun-Hui; HUANG Ming-Ju
2005-01-01
@@ Riboflavin is employed as the photosensitizer of a novel photopolymer material for holographic recording. This material has a broad absorption spectrum range (more than 200nm) due to the addition of this dye. The experimental results show that our material has high diffraction efficiency and large refractive index modulation.The maximum diffraction efficiency of the photopolymer is about 56%. The digital data pages are stored in this medium and the reconstructed data page has a good fidelity, with the bit-error-ratio of about 1.8 × 10-4. It is found that the photopolymer material is suitable for high-density volume holographic digital storage.
Holographic RG flows for gravitational couplings
Energy Technology Data Exchange (ETDEWEB)
Rachwal, L. [ICTP, Strada Costiera 11, 34014 Trieste (Italy); SISSA, via Bonomea 265, 34136 Trieste (Italy); Percacci, R. [SISSA, via Bonomea 265, 34136 Trieste (Italy)
2014-09-11
We present the first attempt to find the holographic interpretation of running of the Newton's constant in 4-dimensional quantum theory. We compute its scale-dependence using functional renormalization group methods based on a Wilsonian momentum cutoff. We show the details of the corresponding holographic RG flow in 5-dimensional spacetime with minimally coupled scalar field in the bulk. In this domain wall setup the scalar potential is found. Solutions of this theory describe RG flows of gravitational coupling with the IR threshold phenomena fully taken into account. (Copyright copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Holographic geometries for condensed matter applications
Keranen, V
2013-01-01
Holographic modeling of strongly correlated many-body systems motivates the study of novel spacetime geometries where the scaling behavior of quantum critical systems is encoded into spacetime symmetries. Einstein-Dilaton-Maxwell theory has planar black brane solutions that exhibit Lifshitz scaling and in some cases hyperscaling violation. Entanglement entropy and Wilson loops in the dual field theory are studied by inserting simple geometric probes involving minimal surfaces into the black brane geometry. Coupling to background matter fields leads to interesting low-energy behavior in holographic models, such as U(1) symmetry breaking and emergent Lifshitz scaling.
Holographic non-Fermi-liquid fixed points.
Faulkner, Tom; Iqbal, Nabil; Liu, Hong; McGreevy, John; Vegh, David
2011-04-28
Techniques arising from string theory can be used to study assemblies of strongly interacting fermions. Via this 'holographic duality', various strongly coupled many-body systems are solved using an auxiliary theory of gravity. Simple holographic realizations of finite density exhibit single-particle spectral functions with sharp Fermi surfaces, of a form distinct from those of the Landau theory. The self-energy is given by a correlation function in an infrared (IR) fixed-point theory that is represented by a two-dimensional anti de Sitter space (AdS(2)) region in the dual gravitational description. Here, we describe in detail the gravity calculation of this IR correlation function.
Real-time wideband holographic surveillance system
Energy Technology Data Exchange (ETDEWEB)
Sheen, David M. (1917 Hood, Richland, WA 99352); Collins, H. Dale (1751 Duluth, Richland, WA 99352); Hall, Thomas E. (8301 W. Entiat Pl., Kennewick, WA 99336); McMakin, Douglas L. (2173 Shasta Ave., Richland, WA 99352); Gribble, R. Parks (1215 Cottonwood Dr., Richland, WA 99352); Severtsen, Ronald H. (1803 Birch Ave., Richland, WA 99352); Prince, James M. (3029 W. 2nd Ave., Apt. F95, Kennewick, WA 99336); Reid, Larry D. (Rt. 1, Box 1291B, Benton City, WA 99320)
1996-01-01
A wideband holographic surveillance system including a transceiver for generating a plurality of electromagnetic waves; antenna for transmitting the electromagnetic waves toward a target at a plurality of predetermined positions in space; the transceiver also receiving and converting electromagnetic waves reflected from the target to electrical signals at a plurality of predetermined positions in space; a computer for processing the electrical signals to obtain signals corresponding to a holographic reconstruction of the target; and a display for displaying the processed information to determine nature of the target. The computer has instructions to apply a three dimensional backward wave algorithm.
Optoelectronic sensors for subsea oil and gas production
McStay, D.; Shiach, G.; Nolan, A.; McAvoy, S.
2007-07-01
The potential for optoelectronic sensor technology to provide the monitoring and control systems required for advanced subsea hydrocarbon production management is described. The utilisation of optoelectronic sensor technology to produce a new class of subsea Christmas Tree with in-built enhanced production monitoring and control systems as well as effective environmental monitoring systems is reported.
Functionalization of Semiconductor Nanomaterials for Optoelectronic Devices And Components
2015-03-04
alternative for single quarter wavelength coating. Previous investigations on Ta2O5 include corrosion protection coating, electrochromic devices ...Functionalization of semiconductor nanomaterials for optoelectronic devices and components 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550-10-1-0136 5c. PROGRAM...Distribution A 13. SUPPLEMENTARY NOTES None 14. ABSTRACT Various semiconductor nanomaterials were functionalized for optoelectronic devices , such
Multiple Quantum Well (MQW) Devices For Monolithic Integrated Optoelectronics
Wood, Thomas H.
1988-05-01
Semiconductor MQWs represent a new technology for opto-electronics. These MQWs have an electroabsorption effect approximately 50 times larger than conventional semiconductors. They are compatible with existing source and detector material systems and produce devices that are compact and high speed, which makes them useful for monolithic integrated optoelectronic devices.
Introduction to the new journal: Frontiers of Optoelectronics in China
Institute of Scientific and Technical Information of China (English)
Bingkun ZHOU
2008-01-01
@@ China, together with the world, has made enormous achievements in the field of optoelectronics in recent years and is still now undergoing the processes of rapid advancement.Chinese Researchers have devoted themselves to finding out ways to solve the problems in optoelectronics, and have made substantial progress theoretically and experimentally.Thus, a platform is needed on which researchers could share their new findings and technological advances in the field of optoelectronics and related disciplines with colleagues around the world.The new launched journal, Frontiers of Optoelectronics in China, aims to serve such a platform that provides a way for scientists all over the world to share the ideas and technologies in the field of optoelectronics.
Full-color holographic 3D printer
Takano, Masami; Shigeta, Hiroaki; Nishihara, Takashi; Yamaguchi, Masahiro; Takahashi, Susumu; Ohyama, Nagaaki; Kobayashi, Akihiko; Iwata, Fujio
2003-05-01
A holographic 3D printer is a system that produces a direct hologram with full-parallax information using the 3-dimensional data of a subject from a computer. In this paper, we present a proposal for the reproduction of full-color images with the holographic 3D printer. In order to realize the 3-dimensional color image, we selected the 3 laser wavelength colors of red (λ=633nm), green (λ=533nm), and blue (λ=442nm), and we built a one-step optical system using a projection system and a liquid crystal display. The 3-dimensional color image is obtained by synthesizing in a 2D array the multiple exposure with these 3 wavelengths made on each 250mm elementary hologram, and moving recording medium on a x-y stage. For the natural color reproduction in the holographic 3D printer, we take the approach of the digital processing technique based on the color management technology. The matching between the input and output colors is performed by investigating first, the relation between the gray level transmittance of the LCD and the diffraction efficiency of the hologram and second, by measuring the color displayed by the hologram to establish a correlation. In our first experimental results a non-linear functional relation for single and multiple exposure of the three components were found. These results are the first step in the realization of a natural color 3D image produced by the holographic color 3D printer.
Observational signatures of holographic models of inflation
P. McFadden; K. Skenderis
2009-01-01
We discuss the phenomenology of recently proposed holographic models of inflation, in which the very early universe is non-geometric and is described by a dual three-dimensional quantum field theory (QFT). We analyze models determined by a specific class of dual QFTs and show that they have the foll
A holographic model for black hole complementarity
Energy Technology Data Exchange (ETDEWEB)
Lowe, David A. [Physics Department, Brown University,Providence, RI 02912 (United States); Thorlacius, Larus [University of Iceland, Science Institute,Dunhaga 3, IS-107, Reykjavik (Iceland); The Oskar Klein Centre for Cosmoparticle Physics,Department of Physics, Stockholm University,AlbaNova University Centre, 10691 Stockholm (Sweden)
2016-12-07
We explore a version of black hole complementarity, where an approximate semiclassical effective field theory for interior infalling degrees of freedom emerges holographically from an exact evolution of exterior degrees of freedom. The infalling degrees of freedom have a complementary description in terms of outgoing Hawking radiation and must eventually decohere with respect to the exterior Hamiltonian, leading to a breakdown of the semiclassical description for an infaller. Trace distance is used to quantify the difference between the complementary time evolutions, and to define a decoherence time. We propose a dictionary where the evolution with respect to the bulk effective Hamiltonian corresponds to mean field evolution in the holographic theory. In a particular model for the holographic theory, which exhibits fast scrambling, the decoherence time coincides with the scrambling time. The results support the hypothesis that decoherence of the infalling holographic state and disruptive bulk effects near the curvature singularity are complementary descriptions of the same physics, which is an important step toward resolving the black hole information paradox.
Aberration coefficients of curved holographic optical elements
Verboven, P. E.; Lagasse, P. E.
1986-11-01
A general formula is derived that gives all aberration terms of holographic optical elements on substrates of any shape. The spherical substrate shape and the planar substrate shape are treated as important special cases. A numerical example illustrates the need of including higher-order aberrations.
Testing and inspecting lens by holographic means
Hildebrand, Bernard P.
1976-01-01
Processes for the accurate, rapid and inexpensive testing and inspecting of oncave and convex lens surfaces through holographic means requiring no beamsplitters, mirrors or overpower optics, and wherein a hologram formed in accordance with one aspect of the invention contains the entire interferometer and serves as both a master and illuminating source for both concave and said convex surfaces to be so tested.
Holographic QCD for H-dibaryon (uuddss)
Suganuma, Hideo
2016-01-01
The H-dibaryon (uuddss) is studied in holographic QCD for the first time. In holographic QCD, four-dimensional QCD, i.e., SU($N_c$) gauge theory with chiral quarks, can be formulated with $S^1$-compactified D4/D8/$\\overline{\\rm D8}$-brane system. In holographic QCD with large $N_c$, all the baryons appear as topological chiral solitons of Nambu-Goldstone bosons and (axial) vector mesons, and the H-dibaryon can be described as an SO(3)-type topological soliton with $B=2$. We derive the low-energy effective theory to describe the H-dibaryon in holographic QCD. The H-dibaryon mass is found to be twice of the $B=1$ hedgehog-baryon mass, $M_{\\rm H} \\simeq 2.00 M_{B=1}^{\\rm HH}$, and is estimated about 1.7GeV, which is smaller than mass of two nucleons (flavor-octet baryons), in the chiral limit.
A holographic model for black hole complementarity
Lowe, David A.; Thorlacius, Larus
2016-12-01
We explore a version of black hole complementarity, where an approximate semiclassical effective field theory for interior infalling degrees of freedom emerges holo-graphically from an exact evolution of exterior degrees of freedom. The infalling degrees of freedom have a complementary description in terms of outgoing Hawking radiation and must eventually decohere with respect to the exterior Hamiltonian, leading to a breakdown of the semiclassical description for an infaller. Trace distance is used to quantify the difference between the complementary time evolutions, and to define a decoherence time. We propose a dictionary where the evolution with respect to the bulk effective Hamiltonian corresponds to mean field evolution in the holographic theory. In a particular model for the holographic theory, which exhibits fast scrambling, the decoherence time coincides with the scrambling time. The results support the hypothesis that decoherence of the infalling holographic state and disruptive bulk effects near the curvature singularity are comple-mentary descriptions of the same physics, which is an important step toward resolving the black hole information paradox.
Propagation phasor approach for holographic image reconstruction
Luo, Wei; Zhang, Yibo; Göröcs, Zoltán; Feizi, Alborz; Ozcan, Aydogan
2016-03-01
To achieve high-resolution and wide field-of-view, digital holographic imaging techniques need to tackle two major challenges: phase recovery and spatial undersampling. Previously, these challenges were separately addressed using phase retrieval and pixel super-resolution algorithms, which utilize the diversity of different imaging parameters. Although existing holographic imaging methods can achieve large space-bandwidth-products by performing pixel super-resolution and phase retrieval sequentially, they require large amounts of data, which might be a limitation in high-speed or cost-effective imaging applications. Here we report a propagation phasor approach, which for the first time combines phase retrieval and pixel super-resolution into a unified mathematical framework and enables the synthesis of new holographic image reconstruction methods with significantly improved data efficiency. In this approach, twin image and spatial aliasing signals, along with other digital artifacts, are interpreted as noise terms that are modulated by phasors that analytically depend on the lateral displacement between hologram and sensor planes, sample-to-sensor distance, wavelength, and the illumination angle. Compared to previous holographic reconstruction techniques, this new framework results in five- to seven-fold reduced number of raw measurements, while still achieving a competitive resolution and space-bandwidth-product. We also demonstrated the success of this approach by imaging biological specimens including Papanicolaou and blood smears.
Photorefractive phase-conjugation digital holographic microscopy
Chang, Chi-Ching; Chan, Huang-Tian; Shiu, Min-Tzung; Chew, Yang-Kun
2015-05-01
In this work, we propose an innovative method for digital holographic microscopy named as photorefractive phaseconjugation digital holographic microscopy (PPCDHM) technique based on the phase conjugation dynamic holographic process in photorefractive BaTiO3 crystal and the retrieval of phase and amplitude of the object wave were performed by a reflection-type digital holographic method. Both amplitude and phase reconstruction benefit from the prior amplification by self-pumped conjugation (SPPC) as they have an increased SNR. The interest of the PPCDHM is great, because its hologram is created by interfered the amplified phase-conjugate wave field generated from a photorefractive phase conjugator (PPC) correcting the phase aberration of the imaging system and the reference wave onto the digital CCD camera. Therefore, a precise three-dimensional description of the object with high SNR can be obtained digitally with only one hologram acquisition. The method requires the acquisition of a single hologram from which the phase distribution can be obtained simultaneously with distribution of intensity at the surface of the object.
Holographic corrections to the Veneziano amplitude
Armoni, Adi; Ireson, Edwin
2017-08-01
We propose a holographic computation of the 2 → 2 meson scattering in a curved string background, dual to a QCD-like theory. We recover the Veneziano amplitude and compute a perturbative correction due to the background curvature. The result implies a small deviation from a linear trajectory, which is a requirement of the UV regime of QCD.
Holographic memories with encryption-selectable function
Su, Wei-Chia; Lee, Xuan-Hao
2006-03-01
Volume holographic storage has received increasing attention owing to its potential high storage capacity and access rate. In the meanwhile, encrypted holographic memory using random phase encoding technique is attractive for an optical community due to growing demand for protection of information. In this paper, encryption-selectable holographic storage algorithms in LiNbO 3 using angular multiplexing are proposed and demonstrated. Encryption-selectable holographic memory is an advance concept of security storage for content protection. It offers more flexibility to encrypt the data or not optionally during the recording processes. In our system design, the function of encryption and non-encryption storage is switched by a random phase pattern and a uniform phase pattern. Based on a 90-degree geometry, the input patterns including the encryption and non-encryption storage are stored via angular multiplexing with reference plane waves at different incident angles. Image is encrypted optionally by sliding the ground glass into one of the recording waves or removing it away in each exposure. The ground glass is a key for encryption. Besides, it is also an important key available for authorized user to decrypt the encrypted information.
Holographic Lovelock gravities and black holes
de Boer, J.; Kulaxizi, M.; Parnachev, A.
2010-01-01
We study holographic implications of Lovelock gravities in AdS spacetimes. For a generic Lovelock gravity in arbitrary spacetime dimensions we formulate the existence condition of asymptotically AdS black holes. We consider small fluctuations around these black holes and determine the constraint on
Pattern recognition with magnonic holographic memory device
Energy Technology Data Exchange (ETDEWEB)
Kozhevnikov, A.; Dudko, G.; Filimonov, Y. [Kotel' nikov Institute of Radioengineering and Electronics of Russian Academy of Sciences, Saratov Branch, Saratov 410019 (Russian Federation); Gertz, F.; Khitun, A. [Electrical Engineering Department, University of California - Riverside, Riverside, California 92521 (United States)
2015-04-06
In this work, we present experimental data demonstrating the possibility of using magnonic holographic devices for pattern recognition. The prototype eight-terminal device consists of a magnetic matrix with micro-antennas placed on the periphery of the matrix to excite and detect spin waves. The principle of operation is based on the effect of spin wave interference, which is similar to the operation of optical holographic devices. Input information is encoded in the phases of the spin waves generated on the edges of the magnonic matrix, while the output corresponds to the amplitude of the inductive voltage produced by the interfering spin waves on the other side of the matrix. The level of the output voltage depends on the combination of the input phases as well as on the internal structure of the magnonic matrix. Experimental data collected for several magnonic matrixes show the unique output signatures in which maxima and minima correspond to specific input phase patterns. Potentially, magnonic holographic devices may provide a higher storage density compare to optical counterparts due to a shorter wavelength and compatibility with conventional electronic devices. The challenges and shortcoming of the magnonic holographic devices are also discussed.
Monopole correlations in holographically flavored liquids
Iqbal, N.
2015-01-01
Many-body systems with a conserved U(1) current in (2+1) dimensions may be probed by weakly gauging this current and studying correlation functions of magnetic monopole operators in the resulting dynamical gauge theory. We study such monopole correlations in holographic liquids with fundamental flav
Heterodyne holographic microscopy of gold particles
Atlan, Michael; Desbiolles, Pierre; Absil, Emilie; Tessier, Gilles; Coppey-Moisan, Maité
2007-01-01
We report experimental results on heterodyne holographic microscopy of subwavelength-sized gold particles. The apparatus uses continuous green laser illumination of the metal beads in a total internal reflection configuration for dark-field operation. Detection of the scattered light at the illumination wavelength on a charge-coupled device array detector enables 3D localization of brownian particles in water
Implantable optoelectronic probes for in vivo optogenetics
Iseri, Ege; Kuzum, Duygu
2017-06-01
More than a decade has passed since optics and genetics came together and lead to the emerging technologies of optogenetics. The advent of light-sensitive opsins made it possible to optically trigger the neurons into activation or inhibition by using visible light. The importance of spatiotemporally isolating a segment of a neural network and controlling nervous signaling in a precise manner has driven neuroscience researchers and engineers to invest great efforts in designing high precision in vivo implantable devices. These efforts have focused on delivery of sufficient power to deep brain regions, while monitoring neural activity with high resolution and fidelity. In this review, we report the progress made in the field of hybrid optoelectronic neural interfaces that combine optical stimulation with electrophysiological recordings. Different approaches that incorporate optical or electrical components on implantable devices are discussed in detail. Advantages of various different designs as well as practical and fundamental limitations are summarized to illuminate the future of neurotechnology development.
Optoelectronic date acquisition system based on FPGA
Li, Xin; Liu, Chunyang; Song, De; Tong, Zhiguo; Liu, Xiangqing
2015-11-01
An optoelectronic date acquisition system is designed based on FPGA. FPGA chip that is EP1C3T144C8 of Cyclone devices from Altera corporation is used as the centre of logic control, XTP2046 chip is used as A/D converter, host computer that communicates with the date acquisition system through RS-232 serial communication interface are used as display device and photo resistance is used as photo sensor. We use Verilog HDL to write logic control code about FPGA. It is proved that timing sequence is correct through the simulation of ModelSim. Test results indicate that this system meets the design requirement, has fast response and stable operation by actual hardware circuit test.
Electroactive and Optoelectronically Active Graphene Nanofilms
DEFF Research Database (Denmark)
Chi, Qijin
As an atomic-scale-thick two-dimensional material, graphene has emerged as one of the most miracle materials and has generated intensive interest in physics, chemistry and even biology in the last decade [1, 2]. Nanoscale engineering and functionalization of graphene is a crucial step for many...... applications ranging from catalysis, electronic devices, sensors to advanced energy conversion and storage [3]. This talk highlights our recent studies on electroactive and optoelectronically active graphene ultrathin films for chemical sensors and energy technology. The presentation includes a general theme...... for functionalization of graphene nanosheets, followed by showing several case studies. Our systems cover redox-active nanoparticles, electroactive supramolecular ensembles and redox enzymes which are integrated with graphene nanosheets as building blocks for the construction of functional thin films or graphene papers....
Optoelectronic properties of natural cyanin dyes.
Calzolari, A; Varsano, D; Ruini, A; Catellani, A; Tel-Vered, R; Yildiz, H B; Ovits, O; Willner, I
2009-07-30
An integrated theoretical/experimental study of the natural cyanin dye is presented in terms of its structural and optoelectronic properties for different gas-phase and prototypical device configurations. Our microscopic analysis reveals the impact of hydration and hydroxylation reactions, as well as of the attached sugar, on ground and optically excited states, and it illustrates the visible-light harvesting capability of the dye. Our optical experiments at different and controlled pH concentrations allow for a direct comparison with theoretical results. We analyze the many different contributions to photocurrent of the various portions of a prototypical device and, as a proof of principle, we propose the addition of specific ligands to control the increase of the photocurrent yield in the cyanin-based electrochemical device.
Nanoscale selective area epitaxy for optoelectronic devices
Elarde, V. C.; Coleman, J. J.
Self-assembled quantum dots have been heavily researched in recent years because of the potential applications to quantum electronic and optoelectronic devices they present. The non-uniformity and random ordering resulting from the self-assembly processes, however, are detrimental to potential applications, prohibiting the type of engineering control necessary for complex systems. The work presented in this document has sought to overcome the limitations of self-assembly by combining selective area epitaxy via MOCVD with high-resolution electron beam lithography to achieve lateral control over semiconductor structures at the nanometer scale. Two different structures are presented. The first is patterned quantum dots which improve on the uniformity and order of similar self-assembled quantum dots. The second is an entirely novel structure, the nanopore active layer, which demonstrates the potential for this process to extend beyond the constraints of self-assembly. Experimental and theoretical results for both structures are presented.
Seeing smells: development of an optoelectronic nose
Directory of Open Access Journals (Sweden)
Kenneth S. Suslick
2007-06-01
Full Text Available The development of an array of chemically-responsive dyes on a porous membrane and in its use as a general sensor for odors and volatile organic compounds (VOCs is reviewed. These colorimetric sensor arrays (CSA act as an "optoelectronic nose" by using an array of multiple dyes whose color changes are based on the full range of intermolecular interactions. The CSA is digitally imaged before and after exposure and the resulting difference map provides a digital fingerprint for any VOC or mixture of odorants. The result is an enormous increase in discriminatory power among odorants compared to prior electronic nose technologies. For the detection of biologically important analytes, including amines, carboxylic acids, and thiols, high sensitivities (ppbv have been demonstrated. The array is essentially non-responsive to changes in humidity due to the hydrophobicity of the dyes and membrane.
Electrodes for Microfluidic Integrated Optoelectronic Tweezers
Directory of Open Access Journals (Sweden)
Kuo-Wei Huang
2011-01-01
Full Text Available We report on two types of electrodes that enable the integration of optoelectronic tweezers (OETs with multilayer poly(dimethylsilane- (PDMS- based microfluidic devices. Both types of electrodes, Au-mesh and single-walled carbon nanotube- (SWNT- embedded PDMS thin film, are optically transparent, electrically conductive, and can be mechanically deformed and provide interfaces to form strong covalent bonding between an OET device and PDMS through standard oxygen plasma treatment. Au-mesh electrodes provide high electrical conductivity and high transparency but are lack of flexibility and allow only small deformation. On the other hand, SWNT-embedded PDMS thin film electrodes provide not only electrical conductivity but also optical transparency and can undergo large mechanical deformation repeatedly without failure. This enables, for the first time, microfluidic integrated OET with on-chip valve and pump functions, which is a critical step for OET-based platforms to conduct more complex and multistep biological and biochemical analyses.
Optoelectronic circuits in nanometer CMOS technology
Atef, Mohamed
2016-01-01
This book describes the newest implementations of integrated photodiodes fabricated in nanometer standard CMOS technologies. It also includes the required fundamentals, the state-of-the-art, and the design of high-performance laser drivers, transimpedance amplifiers, equalizers, and limiting amplifiers fabricated in nanometer CMOS technologies. This book shows the newest results for the performance of integrated optical receivers, laser drivers, modulator drivers and optical sensors in nanometer standard CMOS technologies. Nanometer CMOS technologies rapidly advanced, enabling the implementation of integrated optical receivers for high data rates of several Giga-bits per second and of high-pixel count optical imagers and sensors. In particular, low cost silicon CMOS optoelectronic integrated circuits became very attractive because they can be extensively applied to short-distance optical communications, such as local area network, chip-to-chip and board-to-board interconnects as well as to imaging and medical...
Integrated NEMS and optoelectronics for sensor applications.
Energy Technology Data Exchange (ETDEWEB)
Czaplewski, David A.; Serkland, Darwin Keith; Olsson, Roy H., III; Bogart, Gregory R. (Symphony Acoustics, Rio Rancho, NM); Krishnamoorthy, Uma; Warren, Mial E.; Carr, Dustin Wade (Symphony Acoustics, Rio Rancho, NM); Okandan, Murat; Peterson, Kenneth Allen
2008-01-01
This work utilized advanced engineering in several fields to find solutions to the challenges presented by the integration of MEMS/NEMS with optoelectronics to realize a compact sensor system, comprised of a microfabricated sensor, VCSEL, and photodiode. By utilizing microfabrication techniques in the realization of the MEMS/NEMS component, the VCSEL and the photodiode, the system would be small in size and require less power than a macro-sized component. The work focused on two technologies, accelerometers and microphones, leveraged from other LDRD programs. The first technology was the nano-g accelerometer using a nanophotonic motion detection system (67023). This accelerometer had measured sensitivity of approximately 10 nano-g. The Integrated NEMS and optoelectronics LDRD supported the nano-g accelerometer LDRD by providing advanced designs for the accelerometers, packaging, and a detection scheme to encapsulate the accelerometer, furthering the testing capabilities beyond bench-top tests. A fully packaged and tested die was never realized, but significant packaging issues were addressed and many resolved. The second technology supported by this work was the ultrasensitive directional microphone arrays for military operations in urban terrain and future combat systems (93518). This application utilized a diffraction-based sensing technique with different optical component placement and a different detection scheme from the nano-g accelerometer. The Integrated NEMS LDRD supported the microphone array LDRD by providing custom designs, VCSELs, and measurement techniques to accelerometers that were fabricated from the same operational principles as the microphones, but contain proof masses for acceleration transduction. These devices were packaged at the end of the work.
Holographic dynamics from multiscale entanglement renormalization ansatz
Chua, Victor; Passias, Vasilios; Tiwari, Apoorv; Ryu, Shinsei
2017-05-01
The multiscale entanglement renormalization ansatz (MERA) is a tensor network based variational ansatz that is capable of capturing many of the key physical properties of strongly correlated ground states such as criticality and topological order. MERA also shares many deep relationships with the AdS/CFT (gauge-gravity) correspondence by realizing a UV complete holographic duality within the tensor networks framework. Motivated by this, we have repurposed the MERA tensor network as an analysis tool to study the real-time evolution of the 1D transverse Ising model in its low-energy excited state sector. We performed this analysis by allowing the ancilla qubits of the MERA tensor network to acquire quantum fluctuations, which yields a unitary transform between the physical (boundary) and ancilla qubit (bulk) Hilbert spaces. This then defines a reversible quantum circuit, which is used as a "holographic transform" to study excited states and their real-time dynamics from the point of the bulk ancillae. In the gapped paramagnetic phase of the transverse field Ising model, we demonstrate the holographic duality between excited states induced by single spin-flips (Ising "magnons") acting on the ground state and single ancilla qubit spin flips. The single ancillae qubit excitation is shown to be stable in the bulk under real-time evolution and hence defines a stable holographic quasiparticle, which we have named the "hologron." Their bulk 2D Hamiltonian, energy spectrum, and dynamics within the MERA network are studied numerically. The "dictionary" between the bulk and boundary is determined and realizes many features of the holographic correspondence in a non-CFT limit of the boundary theory. As an added spin-off, this dictionary together with the extension to multihologron sectors gives us a systematic way to construct quantitatively accurate low-energy effective Hamiltonians.
Integral optoelectronic switch based on DMOS-transistors
Directory of Open Access Journals (Sweden)
Politanskyy L. F.
2008-12-01
Full Text Available The characteristics of optoelectronic couples photodiodes-DMOS-transistor are studied in the paper. There was developed a mathematical model of volt-ampere characteristic of the given optoelectronic couple which allows to determine interrelation of its electric parameters with constructive and electrophysical parameters of photodiodes and DMOS-transistors. There was suggested a construction of integral optoelectronic switch, based on DMOS-transistors on the silicon with dielectric insulation structures (SDIS. Possible is the optic control of executive devices, connected both to the source and drain circuits of the switching transistor.
A Study of the H-dibaryon in Holographic QCD
Matsumoto, Kohei; Suganuma, Hideo
2016-01-01
We study the H-dibaryon (uuddss) in holographic QCD for the first time. Holographic QCD is derived from a QCD-equivalent D-brane system in the superstring theory via the gauge/gravity correspondence. In holographic QCD, all baryons appear as topological chiral solitons of Nambu-Goldstone bosons and (axial) vector mesons. In this framework, the H-dibaryon can be described as an SO(3)-type hedgehog state. In this paper, we present the formalism of the H-dibaryon in holographic QCD, and perform the calculation to investigate its properties in the chiral limit.
Diarylethene Materials for Rewritable Volume Holographic Data Storage
Institute of Scientific and Technical Information of China (English)
刘国栋; 何庆声; 丁德华; 邬敏贤; 金国藩; 蒲守智; 张复实; 刘学东; 袁鹏
2003-01-01
The photochromic diarylethene, 1,2-bis(2-methyl-5-(4-formyIphenyl)-thien-3-yl)perfluorocyclopentene ( 1 a) is studied and its applicable potential in rewritable volume holographic data storage is verified. Holographic recording films of 10-μm thickness have been fabricated. The refractive index modulation (△n = 1.15 × 10-3) between the open- and close-ring forms is detected to be large enough so that the films are suitable for the production of volume holographic storage. The experiments of angle multiplexing and rewriting holograms show that the materials are fit for volume holographic data storage.
The compact and inexpensive arrowhead setup for holographic interferometry
Energy Technology Data Exchange (ETDEWEB)
Ladera, Celso L; Donoso, Guillermo, E-mail: clladera@usb.v [Departamento de Fisica, Universidad Simon BolIvar, Apdo. 89000, Caracas 1086 (Venezuela, Bolivarian Republic of)
2011-07-15
Hologram recording and holographic interferometry are intrinsically sensitive to phase changes, and therefore both are easily perturbed by minuscule optical path perturbations. It is therefore very convenient to bank on holographic setups with a reduced number of optical components. Here we present a compact off-axis holographic setup that requires neither a collimator nor a beam-splitter, and whose layout is reminiscent of an arrowhead. We show that this inexpensive setup is a good alternative for the study and applications of scientific holography by measuring small displacements and deformations of a body. The arrowhead setup will be found particularly useful for holography and holographic interferometry experiments and projects in teaching laboratories.
HOMES - Holographic Optical Method for Exoplanet Spectroscopy Project
National Aeronautics and Space Administration — HOMES (Holographic Optical Method for Exoplanet Spectroscopy) is a space telescope designed for exoplanet discovery. Its double dispersion architecture employs a...
A Holographic Proof of R\\'enyi Entropic Inequalities
Nakaguchi, Yuki
2016-01-01
We prove R\\'enyi entropic inequalities in a holographic setup based on the recent proposal for the holographic formula of R\\'enyi entropies. Regarding the R\\'enyi parameter as an inverse temperature, we reformulate the entropies in analogy with statistical mechanics, which provides us a concise interpretation of the inequalities as the positivities of entropy, energy and heat capacity. This analogy also makes clear a thermodynamic structure in deriving the holographic formula. As a by-product of the proof we obtain a holographic formula to calculate the quantum fluctuation of the modular Hamiltonian. A few examples of the capacity of entanglement are examined in detail.
Magnetometer Based on Optoelectronic Microwave Oscillator
Maleki, Lute; Strekalov, Dmitry; Matsko, Andrey
2005-01-01
proposed instrument, intended mainly for use as a magnetometer, would include an optoelectronic oscillator (OEO) stabilized by an atomic cell that could play the role of a magnetically tunable microwave filter. The microwave frequency would vary with the magnetic field in the cell, thereby providing an indication of the magnetic field. The proposed magnetometer would offer a combination of high accuracy and high sensitivity, characterized by flux densities of less than a picotesla. In comparison with prior magnetometers, the proposed magnetometer could, in principle, be constructed as a compact, lightweight instrument: It could fit into a package of about 10 by 10 by 10 cm and would have a mass <0.5 kg. As described in several prior NASA Tech Briefs articles, an OEO is a hybrid of photonic and electronic components that generates highly spectrally pure microwave radiation, and optical radiation modulated by the microwave radiation, through direct conversion between laser light and microwave radiation in an optoelectronic feedback loop. As used here, "atomic cell" signifies a cell containing a vapor, the constituent atoms of which can be made to undergo transitions between quantum states, denoted hyperfine levels, when excited by light in a suitable wavelength range. The laser light must be in this range. The energy difference between the hyperfine levels defines the microwave frequency. In the proposed instrument (see figure), light from a laser would be introduced into an electro-optical modulator (EOM). Amplitude-modulated light from the exit port of the EOM would pass through a fiber-optic splitter having two output branches. The light in one branch would be sent through an atomic cell to a photodiode. The light in the other branch would constitute the microwave-modulated optical output. Part of the light leaving the atomic cell could also be used to stabilize the laser at a frequency in the vicinity of the desired hyperfine or other quantum transition. The
Optoelectronic Infrastructure for RF/Optical Phased Arrays Project
National Aeronautics and Space Administration — Optoelectronic integrated holds the key to higher performance, reduced mass and radiation-hard space systems. A special need is increased flexibility of phased...
Device-packaging method and apparatus for optoelectronic circuits
Energy Technology Data Exchange (ETDEWEB)
Zortman, William A.; Henry, Michael David; Jarecki, Jr., Robert L.
2017-04-25
An optoelectronic device package and a method for its fabrication are provided. The device package includes a lid die and an active die that is sealed or sealable to the lid die and in which one or more optical waveguides are integrally defined. The active die includes one or more active device regions, i.e. integral optoelectronic devices or etched cavities for placement of discrete optoelectronic devices. Optical waveguides terminate at active device regions so that they can be coupled to them. Slots are defined in peripheral parts of the active dies. At least some of the slots are aligned with the ends of integral optical waveguides so that optical fibers or optoelectronic devices inserted in the slots can optically couple to the waveguides.
Opto-electronic devices from block copolymers and their oligomers.
Hadziioannou, G
1997-01-01
This paper presents research activities towards the development of polymer materials and devices for optoelectronics, An approach to controlling the conjugation length and transferring the luminescence properties of organic molecules to polymers through black copolymers containing well-defined conju
Optoelectronic Infrastructure for RF/Optical Phased Arrays Project
National Aeronautics and Space Administration — Optoelectronic integrated circuits offer radiation-hard solutions for satellite systems with much improved SWPB (size, weight, power and bandwidth). The phased array...
Optoelectronic Device Integration in Silicon (OpSIS)
2015-10-26
Delaware in the development of fundamental design tools and methodologies for optoelectronic devices in silicon photonics. We proposed to develop...THIS PAGE U 19b. TELEPHONE NUMBER (Include area code) 302-831-4241 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std . Z39.18 Adobe...10-1-0439 Prime Award Institution: University of Washington Subaward Institution: University of Delaware Title: Optoelectronic Device
Optoelectronic device with nanoparticle embedded hole injection/transport layer
Wang, Qingwu [Chelmsford, MA; Li, Wenguang [Andover, MA; Jiang, Hua [Methuen, MA
2012-01-03
An optoelectronic device is disclosed that can function as an emitter of optical radiation, such as a light-emitting diode (LED), or as a photovoltaic (PV) device that can be used to convert optical radiation into electrical current, such as a photovoltaic solar cell. The optoelectronic device comprises an anode, a hole injection/transport layer, an active layer, and a cathode, where the hole injection/transport layer includes transparent conductive nanoparticles in a hole transport material.
Metal-dielectric hybrid surfaces as integrated optoelectronic interfaces
Energy Technology Data Exchange (ETDEWEB)
Narasimhan, Vijay K.; Hymel, Thomas M.; Lai, Ruby A.; Cui, Yi
2017-01-03
An optoelectronic device has a hybrid metal-dielectric optoelectronic interface including an array of nanoscale dielectric resonant elements (e.g., nanopillars), and a metal film disposed between the dielectric resonant elements and below a top surface of the resonant elements such that the dielectric resonant elements protrude through the metal film. The device may also include an anti-reflection coating. The device may further include a metal film layer on each of the dielectric resonant elements.
Biometric identification using holographic radar imaging techniques
McMakin, Douglas L.; Sheen, David M.; Hall, Thomas E.; Kennedy, Mike O.; Foote, Harlen P.
2007-04-01
Pacific Northwest National Laboratory researchers have been at the forefront of developing innovative screening systems to enhance security and a novel imaging system to provide custom-fit clothing using holographic radar imaging techniques. First-of-a-kind cylindrical holographic imaging systems have been developed to screen people at security checkpoints for the detection of concealed, body worn, non-metallic threats such as plastic and liquid explosives, knifes and contraband. Another embodiment of this technology is capable of obtaining full sized body measurements in near real time without the person under surveillance removing their outer garments. Radar signals readily penetrate clothing and reflect off the water in skin. This full body measurement system is commercially available for best fitting ready to wear clothing, which was the first "biometric" application for this technology. One compelling feature of this technology for security biometric applications is that it can see effectively through disguises, appliances and body hair.
Holographic Mutual Information for Singular Surfaces
Mozaffar, M Reza Mohammadi; Omidi, Farzad
2015-01-01
We study corner contributions to holographic mutual information for entangling regions composed of a set of disjoint sectors of a single infinite circle in three-dimensional conformal field theories. In spite of the UV divergence of holographic mutual information, it exhibits a first order phase transition. We show that tripartite information is also divergent for disjoint sectors, which is in contrast with the well-known feature of tripartite information being finite even when entangling regions share boundaries. We also verify the locality of corner effects by studying mutual information between regions separated by a sharp annular region. Possible extensions to higher dimensions and hyperscaling violating geometries is also considered for disjoint sectors.
Holographic Hall conductivities from dyonic backgrounds
Lindgren, Jonathan; Taliotis, Anastasios; Vanhoof, Joris
2015-01-01
We develop a general framework for computing the holographic 2-point functions and the corresponding conductivities in asymptotically locally AdS backgrounds with an electric charge density, a constant magentic field, and possibly non-trivial scalar profiles, for a broad class of Einstein-Maxwell-Axion-Dilaton theories, including certain Chern-Simons terms. Holographic renormalization is carried out for any theory in this class and the computation of the renormalized AC conductivities at zero spatial momentum is reduced to solving a single decoupled first order Riccati equation. Moreover, we develop a first order fake supergravity formulalism for dyonic renormalization group flows in four dimensions, allowing us to construct analytically infinite families of such backgrounds by specifying a superpotential at will. These RG flows interpolate between AdS$_4$ in the UV and a hyperscaling violating Lifshitz geometry in the IR with exponents $1
Holographic bound in covariant loop quantum gravity
Tamaki, Takashi
2016-01-01
We investigate puncture statistics based on the covariant area spectrum in loop quantum gravity. First, we consider Maxwell-Boltzmann statistics with a Gibbs factor for punctures. We establish formulae which relate physical quantities such as horizon area to the parameter characterizing holographic degrees of freedom. We also perform numerical calculations and obtain consistency with these formulae. These results tell us that the holographic bound is satisfied in the large area limit and correction term of the entropy-area law can be proportional to the logarithm of the horizon area. Second, we also consider Bose-Einstein statistics and show that the above formulae are also useful in this case. By applying the formulae, we can understand intrinsic features of Bose-Einstein condensate which corresponds to the case when the horizon area almost consists of punctures in the ground state. When this phenomena occurs, the area is approximately constant against the parameter characterizing the temperature. When this ...
Holographic entanglement entropy in the nonconformal medium
Park, Chanyong
2015-01-01
We investigate holographically the entanglement entropy of a nonconformal medium whose dual geometry is described by an Einstein-Maxwell-dilaton theory. Due to an additional conserved charge corresponding to the number operator in the dual field theory, its thermodynamics is governed by either a grand canonical or canonical ensemble. We calculate thermodynamic quantities of them by using the holographic renormalization. In addition, we study the entanglement entropy of a nonconformal medium. After defining the entanglement chemical potential analogous to the entanglement temperature, we find that the entanglement entropy of a small subsystem satisfies the relation resembling the first law of thermodynamics for the canonical ensemble. We further show that the entanglement chemical potential, unlike the entanglement temperature, is not universal.
Holographic free energy and thermodynamic geometry
Ghorai, Debabrata
2016-01-01
We analytically obtain the free energy and thermodynamic geometry of holographic superconductors in $2+1$-dimensions. The gravitational theory in the bulk dual to this $2+1$-dimensional strongly coupled theory lives in the $3+1$-dimensions and is that of a charged $AdS$ black hole together with a massive charged scalar field. The matching method is applied to obtain the nature of the fields near the horizon using which the holographic free energy is computed through the gauge/gravity duality. The critical temperature is obtained for a set of values of the matching point of the near horizon and the boundary behaviour of the fields. The thermodynamic geometry is then computed from the free energy of the boundary theory. From the divergence of the thermodynamic scalar curvature, the critical temperature is obtained once again. We then compare this result for the critical temperature with that obtained from the matching method.
Holographic Josephson Junction from Massive Gravity
Hu, Ya-Peng; Zeng, Hua-Bi; Zhang, Hai-Qing
2015-01-01
We study the holographic superconductor-normal metal-superconductor (SNS) Josephon junction in the massive gravity. In the homogeneous case of the chemical potential, we find that the graviton mass will make the normal metal-superconductor phase transition harder to take place. In the holographic model of Josephson junction, it is found that the maximal tunneling current will decrease according to the graviton mass. Besides, the coherence length of the junction decreases as well with respect to the graviton mass. If one interprets the graviton mass as the effect of momentum dissipation in the boundary field theory, it indicates that the stronger the momentum dissipation is, the smaller the coherence length is.
Cold holographic matter in the Higgs branch
Itsios, Georgios; Ramallo, Alfonso V
2015-01-01
We study collective excitations of cold (2+1)-dimensional fundamental matter living on a defect of the four-dimensional N=4 super Yang-Mills theory in the Higgs branch. This system is realized holographically as a D3-D5 brane intersection, in which the D5-brane is treated as a probe with a non-zero gauge flux across the internal part of its worldvolume. We study the holographic zero sound mode in the collisionless regime at low temperature and find a simple analytic result for its dispersion relation. We also find the diffusion constant of the system in the hydrodynamic regime at higher temperature. In both cases we study the dependence on the flux parameter which determines the amount of Higgs symmetry breaking. We also discuss the anyonization of this construction.
Reheating of the Universe as holographic thermalization
Kawai, Shinsuke; Nakayama, Yu
2016-08-01
Assuming gauge/gravity correspondence we study reheating of the Universe using its holographic dual. Inflaton decay and thermalisation of the decay products correspond to collapse of a spherical shell and formation of a blackhole in the dual anti-de Sitter (AdS) spacetime. The reheating temperature is computed as the Hawking temperature of the developed blackhole probed by a dynamical boundary, and is determined by the inflaton energy density and the AdS radius, with corrections from the dynamics of the shell collapse. For given initial energy density of the inflaton field the holographic model typically gives lower reheating temperature than the instant reheating scenario, while it is shown to be safely within phenomenological bounds.
Dynamics and observer dependence of holographic screens
Bousso, Raphael; Moosa, Mudassir
2017-02-01
We study the evolution of holographic screens, both generally and in explicit examples, including cosmology and gravitational collapse. A screen H consists of a one-parameter sequence of maximal surfaces called leaves. Its causal structure is nonrelativistic. Each leaf can store all of the quantum information on a corresponding null slice holographically at no more than one bit per Planck area. Therefore, we expect the screen geometry to reflect certain coarse-grained quantities in the quantum gravity theory. In a given spacetime, there are many different screens, which are naturally associated with different observers. We find that this ambiguity corresponds precisely to the free choice of a single function on H . We also consider the background-free construction of H , where the spacetime is not given. The evolution equations then constrain aspects of the full spacetime and the screen's embedding in it.
Holographic Theory of Gravity and Cosmology
Ng, Y Jack
2016-01-01
According to the holographic principle, the maximum amount of information stored in a region of space scales as the area of its two-dimensional surface, like a hologram. We show that the holographic principle can be understood heuristically as originated from quantum fluctuations of spacetime. Applied to cosmology, this consideration leads to a dynamical cosmological constant $\\Lambda$ of the observed magnitude, in agreement with the result obtained for the present and recent cosmic eras, by using unimodular gravity and causal-set theory. By generalizing the concept of entropic gravity, we find a critical acceleration parameter related to $\\Lambda$ in galactic dynamics, and we construct a phenomenological model of dark matter which we call "modified dark matter" (MDM). We provide successful observational tests of MDM at both the galactic and cluster scales. We also discuss the possibility that the quanta of both dark energy and dark matter obey the quantum Boltzmann statistics or infinite statistics as descri...
Note on Zero Temperature Holographic Superfluids
Guo, Minyong; Niu, Chao; Tian, Yu; Zhang, Hongbao
2016-01-01
In this note, we have addressed various issues on zero temperature holographic superfluids. First, inspired by our numerical evidence for the equality between the superfluid density and particle density, we provide an elegant analytic proof for this equality by a boost trick. Second, using not only the frequency domain analysis but also the time domain analysis from numerical relativity, we identify the hydrodynamic normal modes and calculate out the sound speed, which is shown to increase with the chemical potential and saturate to the value predicted by the conformal field theory in the large chemical potential limit. Third, the generic non-thermalization is demonstrated by the fully non-linear time evolution from a non-equilibrium state for our zero temperature holographic superfluid. Furthermore, a conserved Noether charge is proposed in support of this behavior.
Note on zero temperature holographic superfluids
Guo, Minyong; Lan, Shanquan; Niu, Chao; Tian, Yu; Zhang, Hongbao
2016-06-01
In this note, we have addressed various issues on zero temperature holographic superfluids. First, inspired by our numerical evidence for the equality between the superfluid density and particle density, we provide an elegant analytic proof for this equality by a boost trick. Second, using not only the frequency domain analysis but also the time domain analysis from numerical relativity, we identify the hydrodynamic normal modes and calculate out the sound speed, which is shown to increase with the chemical potential and saturate to the value predicted by the conformal field theory in the large chemical potential limit. Third, the generic non-thermalization is demonstrated by the fully nonlinear time evolution from a non-equilibrium state for our zero temperature holographic superfluid. Furthermore, a conserved Noether charge is proposed in support of this behavior.
Riccati equations for holographic 2-point functions
Papadimitriou, Ioannis
2013-01-01
Any second order linear ordinary differential equation can be transformed into a first order non-linear Riccati equation. We argue that the Riccati form of the linearized fluctuation equations that determine the holographic 2-point functions simplifies considerably the numerical computation of such 2-point functions and the corresponding transport coefficients, while it provides a neat criterion for the infrared regularity of the fluctuations. The Riccati form computes directly the response functions, thus eliminating the arbitrary source from the start. We demonstrate the use of the Riccati equation in this context by computing the holographic 2-point functions for the stress tensor and a scalar operator in a number of asymptotically anti de Sitter backgrounds of a bottom up scalar-gravity model. A recipe for numerical computations is provided and applied in some examples. Exact results are obtained in two confining geometries including geometries that belong in the class of IHQCD.
A Simple Holographic Model of Nonlinear Conductivity
Horowitz, Gary T; Santos, Jorge E
2013-01-01
We present a simple analytic gravitational solution which describes the holographic dual of a 2+1-dimensional conductor which goes beyond the usual linear response. In particular it includes Joule heating. We find that the nonlinear frequency-dependent conductivity is a constant. Surprisingly, the pressure remains isotropic. We also apply an electric field to a holographic insulator and show that there is a maximum electric field below which it can remain an insulator. Above this critical value, we argue that it becomes a conductor due to pair creation of charged particles. Finally, we study 1+1 and 3+1 dimensional conductors at the nonlinear level; here exact solutions are not available and a perturbative analysis shows that the current becomes time dependent, but in a way that is captured by a time-dependent effective temperature.
Reheating of the Universe as holographic thermalization
Directory of Open Access Journals (Sweden)
Shinsuke Kawai
2016-08-01
Full Text Available Assuming gauge/gravity correspondence we study reheating of the Universe using its holographic dual. Inflaton decay and thermalisation of the decay products correspond to collapse of a spherical shell and formation of a blackhole in the dual anti-de Sitter (AdS spacetime. The reheating temperature is computed as the Hawking temperature of the developed blackhole probed by a dynamical boundary, and is determined by the inflaton energy density and the AdS radius, with corrections from the dynamics of the shell collapse. For given initial energy density of the inflaton field the holographic model typically gives lower reheating temperature than the instant reheating scenario, while it is shown to be safely within phenomenological bounds.
Reheating of the Universe as holographic thermalization
Energy Technology Data Exchange (ETDEWEB)
Kawai, Shinsuke, E-mail: shinsuke.kawai@gmail.com [Department of Physics, Sungkyunkwan University, Suwon 16419 (Korea, Republic of); Nakayama, Yu [California Institute of Technology, 452-48, Pasadena, CA 91125 (United States); Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, Kashiwa, Chiba 277-8583 (Japan)
2016-08-10
Assuming gauge/gravity correspondence we study reheating of the Universe using its holographic dual. Inflaton decay and thermalisation of the decay products correspond to collapse of a spherical shell and formation of a blackhole in the dual anti-de Sitter (AdS) spacetime. The reheating temperature is computed as the Hawking temperature of the developed blackhole probed by a dynamical boundary, and is determined by the inflaton energy density and the AdS radius, with corrections from the dynamics of the shell collapse. For given initial energy density of the inflaton field the holographic model typically gives lower reheating temperature than the instant reheating scenario, while it is shown to be safely within phenomenological bounds.
Lifshitz Scaling Effects on Holographic Superconductors
Lu, Jun-Wang; Qian, Peng; Zhao, Yue-Yue; Zhang, Xue
2014-01-01
Via numerical and analytical methods, the effects of the Lifshitz dynamical exponent $z$ on holographic superconductors are studied in some detail, including $s$ wave and $p$ wave models. Working in the probe limit, we find that the behaviors of holographic models indeed depend on concrete value of $z$. We obtain the condensation and conductivity in both Lifshitz black hole and soliton backgrounds with general $z$. For both $s$ wave and $p$ wave models in the black hole backgrounds, as $z$ increases, the phase transition becomes more difficult and the growth of conductivity is suppressed. For the Lifshitz soliton backgrounds, when $z$ increases ($z=1,~2,~3$), the critical chemical potential decreases in the $s$ wave cases but increases in the $p$ wave cases. For $p$ wave models in both Lifshitz black hole and soliton backgrounds, the anisotropy between the AC conductivity in different spatial directions is suppressed when $z$ increases. The analytical results uphold the numerical results.
Capability enhancement in compact digital holographic microscopy
Qu, Weijuan; Wen, Yongfu; Wang, Zhaomin; Yang, Fang; Asundi, Anand
2015-03-01
A compact reflection digital holographic microscopy (DHM) system integrated with the light source and optical interferometer is developed for 3D topographic characterization and real-time dynamic inspection for Microelectromechanical systems (MEMS). Capability enhancement methods in lateral resolution, axial resolving range and large field of view for the compact DHM system are presented. To enhance the lateral resolution, the numerical aperture of a reflection DHM system is analyzed and optimum designed. To enhance the axial resolving range, dual wavelengths are used to extend the measuring range. To enable the large field of view, stitching of the measurement results is developed in the user-friendly software. Results from surfaces structures on silicon wafer, micro-optics on fused silica and dynamic inspection of MEMS structures demonstrate applications of this compact reflection digital holographic microscope for technical inspection in material science.
Holographic trace anomaly at finite temperature
Lee, Bum-Hoon; Nam, Siyoung; Park, Chanyong
2017-01-01
Using the holographic renormalization, we investigate the finite temperature and size effect to the energy-momentum tensor of the dual field theory and its renormalization group (RG) flow. Following the anti-de Sitter/conformal field theory correspondence, the dual field theory of the AdS space is well known to be a conformal field theory that has no nontrivial RG flow. Holographically, that theory can be lifted to a finite temperature version by considering a AdS black hole solution. Because the black hole horizon associated with temperature is dimensionful, it breaks the boundary conformal symmetry and leads to a nontrivial RG flow. In this work, we investigate the finite temperature and size correction to a strongly interacting conformal field theory along the Wisonian renormalization group flow.
Hadron Structure in Holographic Quantum Chromodynamics
Lyubovitskij, V. E.; Gutsche, T.; Schmidt, I.
2017-08-01
Hadrons and multiquark states are discussed within the context of holographic quantum chromodynamics. This approach is based on an action that describes the hadron structure with breaking of conformal and chiral symmetry and includes confinement through the presence of a background dilaton field. According to gauge/gravity duality, five-dimensional boson and fermion fields, moving in AdS space, are dual to the four-dimensional fields on the surface of the AdS sphere, which correspond to hadrons. In this framework, the hadron wave functions - the building blocks of the hadron properties - are dual to the profiles of the AdS fields in the fifth (holographic) dimension, which is identified with a scale. As applications, we consider the properties of hadrons and multiquark states.
Spiral holographic imaging through quantum interference
Tang, Jie; Ming, Yang; Hu, Wei; Lu, Yan-qing
2017-07-01
Spiral holographic imaging in the Hong-Ou-Mandel interference scheme is introduced. Using spontaneous parametric down-conversion as a source of photon pairs, we analyze the joint orbital angular momentum spectrum of a reference photon and the photon encoding information of the object. The first-order interference of light beams in standard holographic imaging is replaced by the quantum interference of two-photon probability amplitudes. The difficulty in retrieving the amplitude and phase structure of an unknown photon is thereby avoided as classical interferometric techniques such as optical holography do not apply. Our results show that the full information of the object's transmission function can be recorded in the spiral hologram, which originates directly from the joint orbital angular momentum spectrum. This presents a lateral demonstration of compressive imaging and can potentially be used for remote sensing.
Exploring unconventional capabilities of holographic tweezers
Hernandez, R. J.; Pagliusi, P.; Provenzano, C.; Cipparrone, G.
2011-06-01
We report an investigation of manipulation and trapping capabilities of polarization holographic tweezers. A polarization gradient connected with a modulation of the ellipticity shows an optical force related to the polarization of the light that can influence optically isotropic particles. While in the case of birefringent particles an unconventional trapping in circularly polarized fringes is observed. A liquid crystal emulsion has been adopted to investigate the capabilities of the holographic tweezers. The unusual trapping observed for rotating bipolar nematic droplets has suggested the involvement of the lift hydrodynamic force responsible of the Magnus effect, originating from the peculiar optical force field. We show that the Magnus force which is ignored in the common approach can contribute to unconventional optohydrodynamic trapping and manipulation.
Holographic renormalization and the electroweak precision parameters
Round, Mark
2010-09-01
We study the effects of holographic renormalization on an AdS/QCD inspired description of dynamical electroweak symmetry breaking. Our model is a 5D slice of AdS5 geometry containing a bulk scalar and SU(2)×SU(2) gauge fields. The scalar field obtains a vacuum expectation value (VEV) which represents a condensate that triggers electroweak symmetry breaking. Fermion fields are constrained to live on the UV brane and do not propagate in the bulk. The two-point functions are holographically renormalized through the addition of boundary counterterms. Measurable quantities are then expressed in terms of well-defined physical parameters, free from any spurious dependence on the UV cutoff. A complete study of the precision parameters is carried out and bounds on physical quantities derived. The large-N scaling of results is discussed.
Holographic Renormalisation and the Electroweak Precision Parameters
Round, Mark
2010-01-01
We study the effects of holographic renormalisation on an AdS/QCD inspired description of dynamical electroweak symmetry breaking. Our model is a 5D slice of AdS_5 geometry containing a bulk scalar and SU(2) times SU(2) gauge fields. The scalar field obtains a VEV which represents a condensate that triggers electroweak symmetry breaking. Fermion fields are constrained to live on the UV brane and do not propagate in the bulk. The two-point functions are holographically renormalised through the addition of boundary counterterms. Measurable quantities are then expressed in terms of well defined physical parameters, free from any spurious dependence on the UV cut-off. A complete study of the precision parameters is carried out and bounds on physical quantities derived. The large-N scaling of results is discussed.
Very General Holographic Superconductors and Entanglement Thermodynamics
Dey, Anshuman; Sarkar, Tapobrata
2014-01-01
We construct and analyze holographic superconductors with generalized higher derivative couplings, in single R-charged black hole backgrounds in four and five dimensions. These systems, which we call very general holographic superconductors, have multiple tuning parameters and are shown to exhibit a rich phase structure. We establish the phase diagram numerically as well as by computing the free energy, and then validated the results by calculating the entanglement entropy for these systems. The entanglement entropy is shown to be a perfect indicator of the phase diagram. The differences in the nature of the entanglement entropy in R-charged backgrounds compared to the AdS-Schwarzschild cases are pointed out. We also compute the analogue of the entangling temperature for a subclass of these systems and compare the results with non-hairy backgrounds.
Reheating of the Universe as holographic thermalization
Kawai, Shinsuke
2015-01-01
Assuming gauge/gravity correspondence we study reheating of the Universe using its holographic dual. Inflaton decay and thermalisation of the decay products correspond to collapse of a spherical shell and formation of a blackhole in the dual anti-de Sitter (AdS) spacetime. The reheating temperature is computed as the Hawking temperature of the developed blackhole probed by a dynamical boundary, and is determined by the inflaton energy density and the AdS radius, with corrections from the dynamics of the shell collapse. For given initial energy density of the inflaton field the holographic model gives significantly lower reheating temperature than the instant reheating scenario, while it is shown to be safely within phenomenological bounds.
Revisiting holographic superconductors with hyperscaling violation
Energy Technology Data Exchange (ETDEWEB)
Pan, Qiyuan [Universidade de Sao Paulo, Instituto de Fisica, C.P. 66318, Sao Paulo (Brazil); Hunan Normal University, Department of Physics, Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, Changsha, Hunan (China); Institute of Theoretical Physics, Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Beijing (China); Zhang, Shao-Jun [Universidade de Sao Paulo, Instituto de Fisica, C.P. 66318, Sao Paulo (Brazil)
2016-03-15
We investigate the effect of the hyperscaling violation on the holographic superconductors. In the s-wave model, we find that the critical temperature decreases first and then increases as the hyperscaling violation increases, and the mass of the scalar field will not modify the value of the hyperscaling violation which gives the minimum critical temperature. We analytically confirm the numerical results by using the Sturm-Liouville method with the higher order trial function and improve the previous findings in Fan (J High Energy Phys 09:048, 2013). However, different from the s-wave case, we note that the critical temperature decreases with the increase of the hyperscaling violation in the p-wave model. In addition, we observe that the hyperscaling violation affects the conductivity of the holographic superconductors and changes the expected relation in the gap frequency in both s-wave and p-wave models. (orig.)
Holographic duality from random tensor networks
Hayden, Patrick; Qi, Xiao-Liang; Thomas, Nathaniel; Walter, Michael; Yang, Zhao
2016-01-01
Tensor networks provide a natural framework for exploring holographic duality because they obey entanglement area laws. They have been used to construct explicit simple models realizing many of the interesting structural features of the AdS/CFT correspondence, including the non-uniqueness of bulk operator reconstruction in the boundary theory. In this article, we explore the holographic properties of networks of random tensors. We find that our models obey the Ryu-Takayanagi entropy formula for all boundary regions, whether connected or not, a fact closely related to known properties of the multipartite entanglement of assistance. Moreover, we find that all boundary regions faithfully encode the physics of their entire bulk entanglement wedges, not just their smaller causal wedges. Our method is to interpret the average over random tensors as the partition function of a classical ferromagnetic Ising model, so that the minimal surfaces of Ryu-Takayanagi appear as domain walls. Upon including the analog of a bu...
Holographic dictionary and defects in the bulk
Khramtsov, Mikhail
2016-10-01
We study the holographic dual of the AdS3 spacetime with a conical defect. We calculate the boundary two-point correlator using the holographic Gubser-Klebanov-Polyakov/Witten dictionary for a scalar field in the bulk. We consider the general case, when the conical defect breaks conformal symmetry at the boundary. The results are compared with previous studies based on the geodesic approximation. They are in good agreement for short correlators, and main discrepancy comes in the region of long correlations. It is shown that in the case when the spacetime is the AdS3/ℤN orbifold, both methods give the same result which also produces the result expected from the orbifold CFT.
HOMES Holographic Optical Method for Exoplanet Spectroscopy
Ditto, Thomas D.; McGrew, Stephen P.
2013-09-01
A novel telescope architecture is proposed specifically for the purpose of taking spectra of exoplanets orbiting stars within 10 pc ("the neighborhood"). The primary objective and the secondary spectrograph are holographic optical elements (HOEs) formed on flat membrane substrates of low areal mass that can be transported on cylinder rolls that are compatible with the payload geometry of delivery vehicles. Ribbon-shaped HOEs of up to 100 x 10 meters are contemplated. Computer models are presented with these dimensions. The models predict resolving power better than 10 mas. Because the primary separates wavelengths, we consider coronagraphs that use the divide and conquer strategy of one wavelength at a time. After delivery at the second Lagrange point, the stowed membranes are unfurled into flat holographic optics positioned in a four part formation spanning 1 km of open space.
Hybrid optoelectronic device with multiple bistable outputs
Costazo-Caso, Pablo A.; Jin, Yiye; Gelh, Michael; Granieri, Sergio; Siahmakoun, Azad
2011-01-01
Optoelectronic circuits which exhibit optical and electrical bistability with hysteresis behavior are proposed and experimentally demonstrated. The systems are based on semiconductor optical amplifiers (SOA), bipolar junction transistors (BJT), PIN photodiodes (PD) and laser diodes externally modulated with integrated electro-absorption modulators (LD-EAM). The device operates based on two independent phenomena leading to both electrical bistability and optical bistability. The electrical bistability is due to the series connection of two p-i-n structures (SOA, BJT, PD or LD) in reverse bias. The optical bistability is consequence of the quantum confined Stark effect (QCSE) in the multi-quantum well (MQW) structure in the intrinsic region of the device. This effect produces the optical modulation of the transmitted light through the SOA (or reflected from the PD). Finally, because the optical transmission of the SOA (in reverse bias) and the reflected light from the PD are so small, a LD-EAM modulated by the voltage across these devices are employed to obtain a higher output optical power. Experiments show that the maximum switching frequency is in MHz range and the rise/fall times lower than 1 us. The temporal response is mainly limited by the electrical capacitance of the devices and the parasitic inductances of the connecting wires. The effects of these components can be reduced in current integration technologies.
Colloidal quantum dot materials for infrared optoelectronics
Arinze, Ebuka S.; Nyirjesy, Gabrielle; Cheng, Yan; Palmquist, Nathan; Thon, Susanna M.
2015-09-01
Colloidal quantum dots (CQDs) are an attractive material for optoelectronic applications because they combine flexible, low-cost solution-phase synthesis and processing with the potential for novel functionality arising from their nanostructure. Specifically, the bandgap of films composed of arrays of CQDs can be tuned via the quantum confinement effect for tailored spectral utilization. PbS-based CQDs can be tuned throughout the near and mid-infrared wavelengths and are a promising materials system for photovoltaic devices that harvest non-visible solar radiation. The performance of CQD solar cells is currently limited by an absorption-extraction compromise, whereby photon absorption lengths in the near infrared spectral regime exceed minority carrier diffusion lengths in the bulk films. Several light trapping strategies for overcoming this compromise and increasing the efficiency of infrared energy harvesting will be reviewed. A thin-film interference technique for creating multi-colored and transparent solar cells will be presented, and a discussion of designing plasmonic nanomaterials based on earth-abundant materials for integration into CQD solar cells is developed. The results indicate that it should be possible to achieve high absorption and color-tunability in a scalable nanomaterials system.
Terahertz biochip based on optoelectronic devices
Lu, Ja-Yu; Chen, Li-Jin; Kao, Tzeng-Fu; Chang, Hsu-Hao; Liu, An-Shyi; Yu, Yi-Chun; Wu, Ruey-Beei; Liu, Wei-Sheng; Chyi, Jen-Inn; Pan, Ci-Ling; Tsai, Ming-Cheng; Sun, Chi-Kuang
2005-10-01
The accurate detection of minute amounts of chemical and biological substances has been a major goal in bioanalytical technology throughout the twentieth century. Fluorescence dye labeling detection remains the effective analysis method, but it modifies the surroundings of molecules and lowering the precision of detection. An alternative label free detecting tool with little disturbance of target molecules is highly desired. Theoretical calculations and experiments have demonstrated that many biomolecules have intrinsic resonance due to vibration or rotation level transitions, allowing terahertz (THz)-probing technique as a potential tool for the label-free and noninvasive detection of biomolecules. In this paper, we first ever combined the THz optoelectronic technique with biochip technology to realize THz biosensing. By transferring the edge-coupled photonic transmitter into a thin glass substrate and by integrating with a polyethylene based biochip channel, near field THz detection of the biomolecules is demonstrated. By directly acquiring the absorption micro-spectrum in the THz range, different boiomecules can then be identified according to their THz fingerprints. For preliminary studies, the capability to identity different illicit drug powders is successfully demonstrated. This novel biochip sensing system has the advantages including label-free detection, high selectivity, high sensitivity, ease for sample preparation, and ease to parallel integrate with other biochip functionality modules. Our demonstrated detection capability allows specifying various illicit drug powders with weight of nano-gram, which also enables rapid identification with minute amounts of other important molecules including DNA, biochemical agents in terrorism warfare, explosives, viruses, and toxics.
Assessment of dental plaque by optoelectronic methods
Negrutiu, Meda-Lavinia; Sinescu, Cosmin; Bortun, Cristina Maria; Levai, Mihaela-Codrina; Topala, Florin Ionel; Crǎciunescu, Emanuela Lidia; Cojocariu, Andreea Codruta; Duma, Virgil Florin; Podoleanu, Adrian Gh.
2016-03-01
The formation of dental biofilm follows specific mechanisms of initial colonization on the surface, microcolony formation, development of organized three dimensional community structures, and detachment from the surface. The structure of the plaque biofilm might restrict the penetration of antimicrobial agents, while bacteria on a surface grow slowly and display a novel phenotype; the consequence of the latter is a reduced sensitivity to inhibitors. The aim of this study was to evaluate with different optoelectronic methods the morphological characteristics of the dental biofilm. The study was performed on samples from 25 patients aged between 18 and 35 years. The methods used in this study were Spectral Domain Optical Coherence Tomography (SD-OCT) working at 870 nm for in vivo evaluations and Scanning Electron Microscopy (SEM) for validations. For each patient a sample of dental biofilm was obtained directly from the vestibular surface of the teeth's. SD-OCT produced C- and B-scans that were used to generate three dimensional (3D) reconstructions of the sample. The results were compared with SEM evaluations. The biofilm network was dramatically destroyed after the professional dental cleaning. OCT noninvasive methods can act as a valuable tool for the 3D characterization of dental biofilms.
Emissive polymeric materials for optoelectronic devices
Shiang, Joseph John; Chichak, Kelly Scott; Cella, James Anthony; Lewis, Larry Neil; Janora, Kevin Henry
2011-07-05
Polymers including at least one structural unit derived from a compound of formula I or including at least one pendant group of formula II may be used in optoelectronic devices ##STR00001## wherein R.sup.1, R.sup.3, R.sup.4 and R.sup.6 are independently hydrogen, alkyl, alkoxy, oxaalkyl, alkylaryl, aryl, arylalkyl, heteroaryl, substituted alkyl; substituted alkoxy, substituted oxaalkyl, substituted alkylaryl, substituted aryl, substituted arylalkyl, or substituted heteroaryl; R.sup.1a is hydrogen or alkyl; R.sup.2 is alkylene, substituted alkylene, oxaalkylene, CO, or CO.sub.2; R.sup.2a is alkylene; R.sup.5 is independently at each occurrence hydrogen, alkyl, alkylaryl, aryl, arylalkyl, alkoxy, carboxy, substituted alkyl; substituted alkylaryl, substituted aryl, substituted arylalkyl, or substituted alkoxy, X is halo, triflate, --B(OR.sup.1a).sub.2, or ##STR00002## located at the 2, 5- or 2, 7-positions; and L is derived from phenylpyridine, tolylpyridine, benzothienylpyridine, phenylisoquinoline, dibenzoquinozaline, fluorenylpyridine, ketopyrrole, 2-(1-naphthyl)benzoxazole)), 2-phenylbenzoxazole, 2-phenylbenzothiazole, coumarin, thienylpyridine, phenylpyridine, benzothienylpyridine, 3-methoxy-2-phenylpyridine, thienylpyridine, phenylimine, vinylpyridine, pyridylnaphthalene, pyridylpyrrole, pyridylimidazole, phenylindole, derivatives thereof or combinations thereof.
Single carbon-nanotube photonics and optoelectronics
Kato, Yuichiro K.
2015-03-01
Single-walled carbon nanotubes have unique optical properties as a result of their one-dimensional structure. Not only do they exhibit strong polarization for both absorption and emission, large exciton binding energies allow for room-temperature excitonic luminescence. Furthermore, their emission is in the telecom-wavelengths and they can be directly synthesized on silicon substrates, providing new opportunities for nanoscale photonics and optoelectronics. Here we discuss the use of individual single-walled carbon nanotubes for generation, manipulation, and detection of light on a chip. Their emission properties can be controlled by coupling to silicon photonic structures such as photonic crystal microcavities and microdisk resonators. Simultaneous photoluminescence and photocurrent measurements show that excitons can dissociate spontaneously, enabling photodetection at low bias voltages despite the large binding energies. More recently, we have found that alternating gate-voltages can generate optical pulse trains from individual nanotubes. Ultimately, these results may be combined to achieve further control over photons at the nanoscale. Work supported by KAKENHI, The Canon Foundation, The Asahi Glass Foundation, and JSPS Open Partnership Joint Projects, as well as the Nanotechnology Platform and Photon Frontier Network Program of MEXT, Japan.
Colloidal nanorod heterostructures for photovoltaics and optoelectronics
Shim, Moonsub
2017-05-01
Colloidal quantum dots (QDs) synthesized in versatile, easy-to-process solutions are opening up exciting prospects in multiple areas, especially in biomedical imaging, photovoltaics, solid-state lighting and displays. The success of most of these prospects relies on high-quality heterostructures that improve optical properties. In particular, the core/shell heterostructure with a type I straddling band offset has been indispensable but the applicability is often limited to those exploiting only photoluminescence. QDs and their heterostructures can also be made with anisotropic shapes that allow access to essentially an unlimited number of combinations of size, shape and composition. Structures that allow enhancement of optical properties and physical accessibility for carrier injection/extraction simultaneously can open up new and exciting prospects in photovoltaics and optoelectronics. This topical review focuses on nanorod-based colloidal semiconductor heterostructures. Two-component, type II staggered band offset nanorod heterostructures capable of efficiently separating photoinduced charges are first discussed. Double heterojunction nanorods that contain three different phases are then considered with respect to their novelty and potential as emissive materials in light-emitting diodes. We conclude with an outlook on the possibility of developing colloidal nanorods that contain epitaxial interfaces beyond the conventional semiconductor heterojunctions.
Disordered Holographic Systems I: Functional Renormalization
Adams, Allan
2011-01-01
We study quenched disorder in strongly correlated systems via holography, focusing on the thermodynamic effects of mild electric disorder. Disorder is introduced through a random potential which is assumed to self-average on macroscopic scales. Studying the flow of this distribution with energy scale leads us to develop a holographic functional renormalization scheme. We test this scheme by computing thermodynamic quantities and confirming that the Harris criterion for relevance, irrelevance or marginality of quenched disorder holds.
Holographic phase transitions at finite chemical potential
Mateos, David; Myers, Robert C; Thomson, Rowan M
2007-01-01
Recently holographic techniques have been used to study the thermal properties of N=2 SYM theory, with gauge group SU(Nc) and coupled to Nf Nc Mq there is no phase transition as a function of the temperature and the baryon density is always nonzero. We also compare the present results for the grand canonical ensemble with those for canonical ensemble in which the baryon density is held fixed [1].
Document watermarking based on digital holographic principle
Kim, Chol-Su; Im, Song-Jin
2013-01-01
A new method for document watermarking based on the digital Fourier hologram is proposed. It applies the methods of digital image watermarking based on holographic principle presented previously in several papers into printed documents. Experimental results show that the proposed method can not only meet the demand on invisibility, robustness and non-reproducibility of the document watermark, and but also has other advantages compared with the conventional methods for document securities such as embossed hologram, Lippmann photograph and halftone modulation.
Holographic window for solar power generation
Kasezawa, Toshihiro; Horimai, Hideyoshi; Tabuchi, Hiroshi; Shimura, Tsutomu
2016-12-01
A new photovoltaic generation unit based on the application of holographic technologies called a Holo-Window is proposed in this work. The basic principle and the optical configuration used for the basic experimental unit are described. Suitable fabrication technology for a hologram with the broadband spectrum required to provide the appropriate sunlight capture capability is then discussed. Finally, a laboratory-prototype Holo-Window unit was developed and its performance was evaluated.
Using a portable holographic camera in cosmetology
Bakanas, R.; Gudaitis, G. A.; Zacharovas, S. J.; Ratcliffe, D. B.; Hirsch, S.; Frey, S.; Thelen, A.; Ladrière, N.; Hering, P.
2006-07-01
The HSF-MINI portable holographic camera is used to record holograms of the human face. The recorded holograms are analyzed using a unique three-dimensional measurement system that provides topometric data of the face with resolution less than or equal to 0.5 mm. The main advantages of this method over other, more traditional methods (such as laser triangulation and phase-measurement triangulation) are discussed.
A Stringy (Holographic) Pomeron with Extrinsic Curvature
Qian, Yachao
2014-01-01
We model the soft pomeron in QCD using a scalar Polyakov string with extrinsic curvature in the bottom-up approach of holographic QCD. The overall dipole-dipole scattering amplitude in the soft pomeron kinematics is shown to be sensitive to the extrinsic curvature of the string for finite momentum transfer. The characteristics of the diffractive peak in the differential elastic $pp$ scattering are affected by a small extrinsic curvature of the string.
Phases of holographic d-wave superconductor
Krikun, A.
2015-01-01
We study different phases in the holographic model of d-wave superconductor. These are described by solutions to the classical equations of motion found in different ansatze. Apart from the known homogeneous d-wave superconducting phase we find three new solutions. Two of them represent two distinct families of the spatially modulated solutions, which realize the charge density wave phases in the dual theory. The third one is the new homogeneous phase with nonzero anapole moment. These phases...
Review of holographic superconductors with Weyl corrections
Momeni, Davood; Myrzakulov, Ratbay
2014-01-01
A quick review on the analytical aspects of holographic superconductors (HSC) with Weyl corrections has been presented. Mainly we focus on matching method and variations approaches. Different types of such HSC have been investigated, s-wave, p-wave and St\\'{u}ckelberg ones. We also review the fundamental construction of a p-wave type , in which the non-Abelian gauge field is coupled to the Weyl tensor. The results are compared from numerics to analytical results.
Interacting holographic generalized cosmic Chaplygin gas model
Naji, Jalil
2014-03-01
In this paper we consider a correspondence between the holographic dark energy density and interacting generalized cosmic Chaplygin gas energy density in flat FRW universe. Then, we reconstruct the potential of the scalar field which describe the generalized cosmic Chaplygin cosmology. In the special case we obtain time-dependent energy density and study cosmological parameters. We find stability condition of this model which is depend on cosmic parameter.
Commensurability effects in holographic homogeneous lattices
Andrade, Tomas; Krikun, Alexander
2016-01-01
An interesting application of the gauge/gravity duality to condensed matter physics is the description of a lattice via breaking translational invariance on the gravity side. By making use of global symmetries, it is possible to do so without scarifying homogeneity of the pertinent bulk solutions, which we thus term as "homogeneous holographic lattices." Due to their technical simplicity, these configurations have received a great deal of attention in the last few years and have been shown to...
Some aspects of holographic W-gravity
Li, Wei
2015-01-01
We use the Chern-Simons formulation of higher spin theories in three dimensions to study aspects of holographic W-gravity. Concepts which were useful in studies of pure bulk gravity theories, such as the Fefferman-Graham gauge and the residual gauge transformations, which induce Weyl transformations in the boundary theory and their higher spin generalizations, are reformulated in the Chern-Simons language. Flat connections that correspond to conformal and lightcone gauges in the boundary theory are considered.
Some aspects of holographic W-gravity
Li, Wei; Theisen, Stefan
2015-08-01
We use the Chern-Simons formulation of higher spin theories in three dimensions to study aspects of holographic W-gravity. Concepts which were useful in studies of pure bulk gravity theories, such as the Fefferman-Graham gauge and the residual gauge transformations, which induce Weyl transformations in the boundary theory and their higher spin generalizations, are reformulated in the Chern-Simons language. Flat connections that correspond to conformal and lightcone gauges in the boundary theory are considered.
Master Symmetry for Holographic Wilson Loops
Klose, Thomas; Munkler, Hagen
2016-01-01
We identify the symmetry underlying the recently observed spectral-parameter transformations of holographic Wilson loops alias minimal surfaces in AdS/CFT. The generator of this nonlocal symmetry is shown to furnish a raising operator on the classical Yangian-type charges of symmetric coset models. We explicitly demonstrate how this master symmetry acts on strong-coupling Wilson loops and indicate a possible extension to arbitrary coupling.
Moduli spaces of cold holographic matter
Ammon, Martin; Jensen, Kristan; Kim, Keun-Young; Laia, João N.; O'Bannon, Andy
2012-11-01
We use holography to study (3 + 1)-dimensional {N}=4 supersymmetric Yang-Mills theory with gauge group SU( N c ), in the large- N c and large-coupling limits, coupled to a single massless ( n + 1)-dimensional hypermultiplet in the fundamental representation of SU( N c ), with n = 3, 2, 1. In particular, we study zero-temperature states with a nonzero baryon number charge density, which we call holographic matter. We demonstrate that a moduli space of such states exists in these theories, specifically a Higgs branch parameterized by the expectation values of scalar operators bilinear in the hypermultiplet scalars. At a generic point on the Higgs branch, the R-symmetry and gauge group are spontaneously broken to subgroups. Our holographic calculation consists of introducing a single probe D p-brane into AdS 5 × {{{S}}^5} , with p = 2 n + 1 = 7, 5, 3, introducing an electric flux of the D p-brane worldvolume U(1) gauge field, and then obtaining explicit solutions for the worldvolume fields dual to the scalar operators that parameterize the Higgs branch. In all three cases, we can express these solutions as non-singular self-dual U(1) instantons in a four-dimensional space with a metric determined by the electric flux. We speculate on the possibility that the existence of Higgs branches may point the way to a counting of the microstates producing a nonzero entropy in holographic matter. Additionally, we speculate on the possible classification of zero-temperature, nonzero-density states described holographically by probe D-branes with worldvolume electric flux.
Holographic window for solar power generation
Kasezawa, Toshihiro; Horimai, Hideyoshi; Tabuchi, Hiroshi; Shimura, Tsutomu
2016-08-01
A new photovoltaic generation unit based on the application of holographic technologies called a Holo-Window is proposed in this work. The basic principle and the optical configuration used for the basic experimental unit are described. Suitable fabrication technology for a hologram with the broadband spectrum required to provide the appropriate sunlight capture capability is then discussed. Finally, a laboratory-prototype Holo-Window unit was developed and its performance was evaluated.
Shrinkage measurement for holographic recording materials
Fernández, R.; Gallego, S.; Márquez, A.; Francés, J.; Navarro Fuster, V.; Neipp, C.; Ortuño, M.; Beléndez, A.; Pascual, I.
2017-05-01
There is an increasing demand for new holographic recording materials. One of them are photopolymers, which are becoming a classic media in this field. Their versatility is well known and new possibilities are being created by including new components, such as nanoparticles or dispersed liquid crystal molecules in classical formulations, making them interesting for additional applications in which the thin film preparation and the structural modification have a fundamental importance. Prior to obtaining a wide commercialization of displays based on photopolymers, one of the key aspects is to achieve a complete characterization of them. In this sense, one of the main parameters to estimate and control is the shrinkage of these materials. The volume variations change the angular response of the hologram in two aspects, the angular selectivity and the maximum diffraction efficiency. One criteria for the recording material to be used in a holographic data storage application is the shrinkage, maximum of 0.5%. Along this work, we compare two different methods to measure the holographic recording material shrinkage. The first one is measuring the angle of propagation for both diffracted orders +/-1 when slanted gratings are recorded, so that an accurate value of the grating vector can be calculated. The second one is based on interference measurements at zero spatial frequency limit. We calculate the shrinkage for three different photopolymers: a polyvinyl alcohol acrylamide (PVA/AA) based photopolymer, one of the greenest photopolymers whose patent belongs to the Alicante University called Biophotopol and on the last place a holographic-dispersed liquid crystal photopolymer (H-PDLC).
Holographic cosmological models on the braneworld
Energy Technology Data Exchange (ETDEWEB)
Lepe, Samuel [Instituto de Fisica, Pontificia Universidad Catolica de Valparaiso, Casilla 4950, Valparaiso (Chile); Saavedra, Joel [Instituto de Fisica, Pontificia Universidad Catolica de Valparaiso, Casilla 4950, Valparaiso (Chile)], E-mail: joel.saavedra@ucv.cl; Pena, Francisco [Departamento de Ciencias Fisicas, Facultad de Ingenieria, Ciencias y Administracion, Universidad de la Frontera, Avda. Francisco Salazar 01145, Casilla 54-D, Temuco (Chile)
2009-01-26
In this Letter we have studied a closed universe which a holographic energy on the brane whose energy density is described by {rho}(H)=3c{sup 2}H{sup 2} and we obtain an equation for the Hubble parameter. This equation gave us different physical behavior depending if c{sup 2}>1 or c{sup 2}<1 against of the sign of the brane tension.
Holographic coherent states from random tensor networks
Qi, Xiao-Liang; Yang, Zhao; You, Yi-Zhuang
2017-08-01
Random tensor networks provide useful models that incorporate various important features of holographic duality. A tensor network is usually defined for a fixed graph geometry specified by the connection of tensors. In this paper, we generalize the random tensor network approach to allow quantum superposition of different spatial geometries. We setup a framework in which all possible bulk spatial geometries, characterized by weighted adjacient matrices of all possible graphs, are mapped to the boundary Hilbert space and form an overcomplete basis of the boundary. We name such an overcomplete basis as holographic coherent states. A generic boundary state can be expanded in this basis, which describes the state as a superposition of different spatial geometries in the bulk. We discuss how to define distinct classical geometries and small fluctuations around them. We show that small fluctuations around classical geometries define "code subspaces" which are mapped to the boundary Hilbert space isometrically with quantum error correction properties. In addition, we also show that the overlap between different geometries is suppressed exponentially as a function of the geometrical difference between the two geometries. The geometrical difference is measured in an area law fashion, which is a manifestation of the holographic nature of the states considered.
Holographic interferometry for security and forensic applications
Ambadiyil, Sajan; R. C., Sreelekshmi; Mahadevan Pillai, V. P.; Prabhu, Radhakrishna
2016-10-01
Security holograms having unique 3D images are one of the tools for enhancing the security for product and personnel authentication and anti-counterfeiting. Apart from the high technology that is required, the uniqueness of a 3D object presents a significant additional threshold for the counterfeiting of such security holograms. But, due to the development of 3D printing technology, the hurdles are disabled and allow the chances of counterfeiting. In order to overcome this, holographic interferometry is effectively utilized and the object is recorded twice before and after the state of random object change. At the time of reconstruction, two signal waves generated simultaneously interfere each other, resulting in a fringe modulation. This fringe modulation in 3D image hologram with respect to the random object change is exploited to generate a rigid and unique anticounterfeit feature. Though holographic interferometry techniques are being widely used for the non-destructive evaluation, the applicability of this technology for the security and forensic activity is less exploited. This paper describes our efforts to introduce holographic interferometry in 3D image holograms for security and forensic applications.
A shape dynamical approach to holographic renormalization
Energy Technology Data Exchange (ETDEWEB)
Gomes, Henrique [University of California at Davis, Davis, CA (United States); Gryb, Sean [Utrecht University, Institute for Theoretical Physics, Utrecht (Netherlands); Radboud University Nijmegen, Institute for Mathematics, Astrophysics and Particle Physics, Nijmegen (Netherlands); Koslowski, Tim [University of New Brunswick, Fredericton, NB (Canada); Mercati, Flavio; Smolin, Lee [Perimeter Institute for Theoretical Physics, Waterloo, ON (Canada)
2015-01-01
We provide a bottom-up argument to derive some known results from holographic renormalization using the classical bulk-bulk equivalence of General Relativity and Shape Dynamics, a theory with spatial conformal (Weyl) invariance. The purpose of this paper is twofold: (1) to advertise the simple classical mechanism, trading off gauge symmetries, that underlies the bulk-bulk equivalence of General Relativity and Shape Dynamics to readers interested in dualities of the type of AdS/conformal field theory (CFT); and (2) to highlight that this mechanism can be used to explain certain results of holographic renormalization, providing an alternative to the AdS/CFT conjecture for these cases. To make contact with the usual semiclassical AdS/CFT correspondence, we provide, in addition, a heuristic argument that makes it plausible that the classical equivalence between General Relativity and Shape Dynamics turns into a duality between radial evolution in gravity and the renormalization group flow of a CFT. We believe that Shape Dynamics provides a new perspective on gravity by giving conformal structure a primary role within the theory. It is hoped that this work provides the first steps toward understanding what this new perspective may be able to teach us about holographic dualities. (orig.)
Redshift drift constraints on holographic dark energy
He, Dong-Ze; Zhang, Jing-Fei; Zhang, Xin
2017-03-01
The Sandage-Loeb (SL) test is a promising method for probing dark energy because it measures the redshift drift in the spectra of Lyman- α forest of distant quasars, covering the "redshift desert" of 2 ≲ z ≲ 5, which is not covered by existing cosmological observations. Therefore, it could provide an important supplement to current cosmological observations. In this paper, we explore the impact of SL test on the precision of cosmological constraints for two typical holographic dark energy models, i.e., the original holographic dark energy (HDE) model and the Ricci holographic dark energy (RDE) model. To avoid data inconsistency, we use the best-fit models based on current combined observational data as the fiducial models to simulate 30 mock SL test data. The results show that SL test can effectively break the existing strong degeneracy between the present-day matter density Ωm0 and the Hubble constant H 0 in other cosmological observations. For the considered two typical dark energy models, not only can a 30-year observation of SL test improve the constraint precision of Ωm0 and h dramatically, but can also enhance the constraint precision of the model parameters c and α significantly.
Redshift drift constraints on holographic dark energy
He, Dong-Ze; Zhang, Xin
2016-01-01
The Sandage-Loeb (SL) test is a promising method for probing dark energy because it measures the redshift drift in the spectra of Lyman-$\\alpha$ forest of distant quasars, covering the "redshift desert" of $2\\lesssim z\\lesssim5$, which is not covered by existing cosmological observations. Therefore, it could provide an important supplement to current cosmological observations. In this paper, we explore the impact of SL test on the precision of cosmological constraints for two typical holographic dark energy models, i.e., the original holographic dark energy (HDE) model and the Ricci holographic dark energy (RDE) model. To avoid data inconsistency, we use the best-fit models based on current combined observational data as the fiducial models to simulate 30 mock SL test data. The results show that SL test can effectively break the existing strong degeneracy between the present-day matter density $\\Omega_{m0}$ and the Hubble constant $H_0$ in other cosmological observations. For the considered two typical dark e...
Holographic Interferometry Applications In External Osteosynthesis
Jacquot, P.; Rastogi, P. K.; Pflug, L.
1985-08-01
In order to maintain fragments of fractured bones in a state of immobilization, the use of an external rigid frame has proved to be very advantageous. Confronted by contradictory requirements, the conception of external fixation has, however, been a difficult task. The present paper aims to show, through three examples of varied bearings, the interest of holographic interferometry in external osteosynthesis. The first example deals with the mechanical behavior of a key element of the fixation device the ball joint submitted to realistic loads. The last two examples compare two models of ball joints as to their characteristics of rigidity and of resistance to slipping. Whereas in the former case holographic interferometry primarily fulfills the function of a prelude to the modelization work, in the latter cases it serves to formulate an engineering diagnostic. The findings relate to the remarkable elastic behavior of the ball joint, to the effectiveness of a lightened bowl design, and to the fact that cousin models may behave quite differently as to their resistance to slipping rotations of the bar. In comparison with other experimental methods, holographic interferometry appears to be very competitive and result-oriented and, as such, is expected to multiply applications in similar evaluation tasks.
Magnonic holographic imaging of magnetic microstructures
Gutierrez, D.; Chiang, H.; Bhowmick, T.; Volodchenkov, A. D.; Ranjbar, M.; Liu, G.; Jiang, C.; Warren, C.; Khivintsev, Y.; Filimonov, Y.; Garay, J.; Lake, R.; Balandin, A. A.; Khitun, A.
2017-04-01
We propose and demonstrate a technique for magnetic microstructure imaging via their interaction with propagating spin waves. In this approach, the object of interest is placed on top of a magnetic testbed made of material with low spin wave damping. There are micro-antennas incorporated in the testbed. Two of these antennas are used for spin wave excitation while another one is used for the detecting of inductive voltage produced by the interfering spin waves. The measurements are repeated for different phase differences between the spin wave generating antennas which is equivalent to changing the angle of illumination. The collected data appear as a 3D plot - the holographic image of the object. We present experimental data showing magnonic holographic images of a low-coercivity Si/Co sample, a high-coercivity sample made of SrFe12O19 and a diamagnetic copper sample. We also present images of the three samples consisting of a different amount of SrFe12O19 powder. The imaging was accomplished on a Y3Fe2(FeO4)3 testbed at room temperature. The obtained data reveal the unique magnonic signatures of the objects. Experimental data is complemented by the results of numerical modeling, which qualitatively explain the characteristic features of the images. Potentially, magnonic holographic imaging may complement existing techniques and be utilized for non-destructive in-situ magnetic object characterization. The fundamental physical limits of this approach are also discussed.
Drawing Lines with Light in Holographic Space
Chang, Yin-Ren; Richardson, Martin
2013-02-01
This paper explores the dynamic and expressive possibilities of holographic art through a comparison of art history and technical media such as photography, film and holographic technologies. Examples of modern art and creative expression of time and motions are examined using the early 20th century art movement, Cubism, where subjects are portrayed to be seen simultaneously from different angles. Folding space is represented as subject matter as it can depict space from multiple points of time. The paper also investigates the way holographic art has explored time and space. The lenticular lens-based media reveal a more subjective poetic art in the form of the lyrical images and messages as spectators pass through time, or walk along with the piece of work through an interactive process. It is argued that photographic practice is another example of artistic representation in the form of aesthetic medium of time movement and as such shares a common ground with other dynamic expression that require time based interaction.
Holographic torus entanglement and its RG flow
Bueno, Pablo
2016-01-01
We study the universal contributions to the entanglement entropy (EE) of 2+1d and 3+1d holographic conformal field theories (CFTs) on topologically non-trivial manifolds, focusing on tori. The holographic bulk corresponds to AdS-soliton geometries. We characterize the properties of these regulator-independent EE terms as a function of both the size of the cylindrical entangling region, and the shape of the torus. In 2+1d, in the simple limit where the torus becomes a thin 1d ring, the EE reduces to a shape-independent constant $2\\gamma$. This is twice the EE obtained by bipartitioning an infinite cylinder into equal halves. We study the RG flow of $\\gamma$ by defining a renormalized EE that 1) is applicable to general QFTs, 2) resolves the failure of the area law subtraction, and 3) is inspired by the F-theorem. We find that the renormalized $\\gamma$ decreases monotonically when the holographic CFT is deformed by a relevant operator for all allowed scaling dimensions. We also discuss the question of non-uniqu...
Gravitation from Entanglement in Holographic CFTs
Faulkner, Thomas; Hartman, Thomas; Myers, Robert C; Van Raamsdonk, Mark
2013-01-01
Entanglement entropy obeys a 'first law', an exact quantum generalization of the ordinary first law of thermodynamics. In any CFT with a semiclassical holographic dual, this first law has an interpretation in the dual gravitational theory as a constraint on the spacetimes dual to CFT states. For small perturbations around the CFT vacuum state, we show that the set of such constraints for all ball-shaped spatial regions in the CFT is exactly equivalent to the requirement that the dual geometry satisfy the gravitational equations of motion, linearized about pure AdS. For theories with entanglement entropy computed by the Ryu-Takayanagi formula $S=A/(4G_N)$, we obtain the linearized Einstein equations. For theories in which the vacuum entanglement entropy for a ball is computed by more general Wald functionals, we obtain the linearized equations for the associated higher-curvature theories. Using the first law, we also derive the holographic dictionary for the stress tensor, given the holographic formula for ent...
Holographic renormalization as a canonical transformation
Papadimitriou, Ioannis
2010-01-01
The gauge/string dualities have drawn attention to a class of variational problems on a boundary at infinity, which are not well defined unless a certain boundary term is added to the classical action. In the context of supergravity in asymptotically AdS spaces these problems are systematically addressed by the method of holographic renormalization. We argue that this class of a priori ill defined variational problems extends far beyond the realm of holographic dualities. As we show, exactly the same issues arise in gravity in non asymptotically AdS spaces, in point particles with certain unbounded from below potentials, and even fundamental strings in flat or AdS backgrounds. We show that the variational problem in all such cases can be made well defined by the following procedure, which is intrinsic to the system in question and does not rely on the existence of a holographically dual theory: (i) The first step is the construction of the space of the most general asymptotic solutions of the classical equati...
Bottom-up holographic approach to QCD
Energy Technology Data Exchange (ETDEWEB)
Afonin, S. S. [V. A. Fock Department of Theoretical Physics, Saint Petersburg State University, 1 ul. Ulyanovskaya, 198504 (Russian Federation)
2016-01-22
One of the most known result of the string theory consists in the idea that some strongly coupled gauge theories may have a dual description in terms of a higher dimensional weakly coupled gravitational theory — the so-called AdS/CFT correspondence or gauge/gravity correspondence. The attempts to apply this idea to the real QCD are often referred to as “holographic QCD” or “AdS/QCD approach”. One of directions in this field is to start from the real QCD and guess a tentative dual higher dimensional weakly coupled field model following the principles of gauge/gravity correspondence. The ensuing phenomenology can be then developed and compared with experimental data and with various theoretical results. Such a bottom-up holographic approach turned out to be unexpectedly successful in many cases. In the given short review, the technical aspects of the bottom-up holographic approach to QCD are explained placing the main emphasis on the soft wall model.
Bottom-up holographic approach to QCD
Afonin, S. S.
2016-01-01
One of the most known result of the string theory consists in the idea that some strongly coupled gauge theories may have a dual description in terms of a higher dimensional weakly coupled gravitational theory — the so-called AdS/CFT correspondence or gauge/gravity correspondence. The attempts to apply this idea to the real QCD are often referred to as "holographic QCD" or "AdS/QCD approach". One of directions in this field is to start from the real QCD and guess a tentative dual higher dimensional weakly coupled field model following the principles of gauge/gravity correspondence. The ensuing phenomenology can be then developed and compared with experimental data and with various theoretical results. Such a bottom-up holographic approach turned out to be unexpectedly successful in many cases. In the given short review, the technical aspects of the bottom-up holographic approach to QCD are explained placing the main emphasis on the soft wall model.
Holographic backgrounds from D-brane probes
Moskovic, Micha
2014-01-01
This thesis focuses on the derivation of holographic backgrounds from the field theory side, without using any supergravity equations of motion. Instead, we rely on the addition of probe D-branes to the stack of D-branes generating the background. From the field theory description of the probe branes, one can compute an effective action for the probes (in a suitable low-energy/near-horizon limit) by integrating out the background branes. Comparing this action with the generic probe D-brane action then allows to determine the holographic background dual to the considered field theory vacuum. In the first part, the required pre-requisites of field and string theory are recalled and this strategy to derive holographic backgrounds is explained in more detail on the basic case of D3-branes in flat space probed by a small number of D-instantons. The second part contains our original results, which have already appeared in arXiv:1301.3738, arXiv:1301.7062 and arXiv:1312.0621. We first derive the duals to three conti...
Holographic Wilson loops in anisotropic quark-gluon plasma.
Ageev, Dmitry
2016-10-01
The nonequilibrium properties of the anisotropic quark-gluon plasma are condidered from the holographic viewpoint. Lifshitz-like solution is considered as a holographic dual of anisotropic QGP. The black brane formation in such background is considered as a thermalization in dual theory. As a probe of thermalization we consider rectangular spatial Wilson loops with different orientation.
Holographic Wilson loops in anisotropic quark-gluon plasma.
Directory of Open Access Journals (Sweden)
Ageev Dmitry
2016-01-01
Full Text Available The nonequilibrium properties of the anisotropic quark-gluon plasma are condidered from the holographic viewpoint. Lifshitz-like solution is considered as a holographic dual of anisotropic QGP. The black brane formation in such background is considered as a thermalization in dual theory. As a probe of thermalization we consider rectangular spatial Wilson loops with different orientation.
Digital compositing a full-color holographic animated stereogram
Diamond, Mark C.
1995-02-01
The paper addresses the use of hybrid cinematography, computer graphics, and electronic imaging to create a full color, animated, holographic stereogram for embossed replication. Several methods of stereoscopic techniques for pre-visualization of holographic stereogram subjects are discussed as well.
Reusable holographic velocimetry system based on polarization multiplexing in Bacteriorhodopsin
Koek, W.D.; Chan, V.S.S.; Ooms, T.A.; Bhattacharya, N.; Westerweel, J.; Braat, J.J.M.
2005-01-01
We present a novel holographic particle image velocimetry (HPIV) system using a reversible holographic material as the recording medium. In HPIV the three-dimensional flow field throughout a volume is detected by adding small tracer particles to a normally transparent medium. By recording the
Rewritable azobenzene polyester for polarization holographic data storage
DEFF Research Database (Denmark)
Kerekes, A; Sajti, Sz.; Loerincz, Emoeke;
2000-01-01
Optical storage properties of thin azobenzene side-chain polyester films were examined by polarization holographic measurements. The new amorphous polyester film is the candidate material for the purpose of rewritable holographic memory system. Temporal formation of anisotropic and topographic...... and erasing was tested. The ability of azobenzene polyester for rewriting was found satisfactory after many writing-erasing cycles....
New large-format holographic laboratory in France
Gauchet, Pascal E. P.
1994-01-01
A new holographic laboratory, Photonics 3D, has opened in Lyon, France. Its objectives are many fold: to encourage creative research in the field of holographic imagery, to set up an artist in residence program and to allow the production of very large holograms.
Holographic bounds on the UV cutoff scale in inflationary cosmology
DEFF Research Database (Denmark)
Keski-Vakkuri, Esko; Sloth, Martin Snoager
2003-01-01
We discuss how holographic bounds can be applied to the quantum fluctuations of the inflaton. In general the holographic principle will lead to a bound on the UV cutoff scale of the effective theory of inflation, but it will depend on the coarse-graining prescription involved in calculating...
Depth perception and user interface in digital holographic television
Barabas, James; Jolly, Sundeep; Smalley, Daniel E.; Bove, V. Michael, Jr.
2012-03-01
A holographic television system, featuring realtime incoherent 3D capture and live holographic display is used for experiments in depth perception. Holographic television has the potential to provide more complete visual representations, including latency-free motion parallax and more natural affordances for accommodation. Although this technology has potential to improve realism in many display applications, we investigate benefits in uses where direct vision of a workspace is not possible. Applications of this nature include work with hazardous materials, teleoperation over distance, and laparoscopic surgery. In this study, subjects perform manual 3D object manipulation tasks where they can only see the workspace through holographic closed-circuit television. This study is designed to compare performance at manual tasks using holographic television compared to performance with displays that mimic 2D, and stereoscopic television.
Optical properties of a photopolymer film for digital holographic storage
Shin, Changwon; Kim, Junghoi; Kim, Nam; Lee, Hyojin; Kim, Eunkyoung
2005-09-01
Tir- and mono functional monomers were dispersed in a solution of polysulfone in organic solvent containing a photo initiator and other additives. New photopolymer film was prepared by dispersing acrylic monomer in a polysulfone matrix. The Polysulfone was adopted as a binder since it affords transparent thick films with low dimensional changes during holographic recording. Optical property of the photopolymer showed high diffraction efficiency (>90%) under an optimized optical condition at 532nm laser. The angular selectivity for angular multiplexing page oriented holographic memories (POHMs), the maximum diffraction efficiency of the material during holographic recording, the diffraction efficiency of the films as a function of an incident angle of two beams, exposure energy for saturation of the holographic material and application for holographic data storage will be discussed.
Research on copying system of dynamic multiplex holographic stereograms
Fu, Huaiping; Yang, Hong; Zheng, Tong
2003-05-01
The most important advantage of holographic stereograms over conventional hologram is that they can produce 3D images at any desired scale with movement, holographers in many countries involved in the studies towards it. We began our works in the early 80's and accomplished two research projects automatic system for making synthetic holograms and multiplex synthetic rainbow holograms, Based on these works, a large scale holographic stereogram of an animated goldfish was made by us for practical advertisement. In order to meet the needs of the market, a copying system for making multiplex holographic stereograms, and a special kind of silver halide holographic film developed by us recently. The characteristic of the copying system and the property of the special silver-halide emulsion are introduced in this paper.
Energy Momentum Tensor Correlators in Improved Holographic QCD
Krssak, Martin
2013-01-01
In this thesis, we study the physics of the quark gluon plasma (QGP) using holographic methods borrowed from string theory. We start our discussion by motivating the use of such machinery, explaining how recent experimental results from the LHC and RHIC colliders suggests that the created QGP should be described as a strongly coupled liquid with small but nonvanishing bulk and shear viscosities. We argue that holographic dualities are a very efficient framework for studying transport properties in such a medium. Next, we introduce the underlying physics behind all holographic dualities, the AdS/CFT correspondence, and then motivate the necessity of implementing conformal invariance breaking in them. After this, we present the phenomenologically most successful holographic model of the strong interactions - Improved Holographic QCD (IHQCD). Working within IHQCD, we next move on to calculate energy momentum tensor correlators in the bulk and shear channels of large-Nc Yang-Mills theory. In the shear channel, we...
DC Conductivity of Magnetised Holographic Matter
Donos, Aristomenis; Griffin, Tom; Melgar, Luis
2015-01-01
We consider general black hole solutions of Einstein-Maxwell-scalar theory that are holographically dual to conformal field theories at finite charge density with non-vanishing magnetic fields and local magnetisation currents, which generically break translation invariance explicitly. We show that the thermoelectric DC conductivity of the field theory can be obtained by solving a system of generalised Stokes equations on the black hole horizon. For various examples, including Q-lattices and one-dimensional lattices, we solve the Stokes equations explicitly and obtain expressions for the DC conductivity in terms of the solution at the black hole horizon.
Holographic representation of local bulk operators
Hamilton, A; Lifschytz, G; Lowe, D A; Hamilton, Alex; Kabat, Daniel; Lifschytz, Gilad; Lowe, David A.
2006-01-01
The Lorentzian AdS/CFT correspondence implies a map between local operators in supergravity and non-local operators in the CFT. By explicit computation we construct CFT operators which are dual to local bulk fields in the semiclassical limit. The computation is done for general dimension in global, Poincare and Rindler coordinates. We find that the CFT operators can be taken to have compact support in a region of the complexified boundary whose size is set by the bulk radial position. We show that at finite N the number of independent commuting operators localized within a bulk volume saturates the holographic bound.
A Holographic Model of Quantum Hall Transition
Mezzalira, Andrea
2015-01-01
We consider a phenomenological holographic model, inspired by the D3/D7 system with a 2+1 dimensional intersection, at finite chemical potential and magnetic field. At large 't Hooft coupling the system is unstable and needs regularization; the UV cutoff can be decoupled by considering a certain double scaling limit. At finite chemical potential the model exhibits a phase transition between states with filling fractions plus and minus one--half as the magnetic field is varied. By varying the parameters of the model, this phase transition can be made to happen at arbitrary values of the magnetic field.
Holographic Lattices Give the Graviton a Mass
Blake, Mike; Vegh, David
2014-01-01
We discuss the DC conductivity of holographic theories with translational invariance broken by a background lattice. We show that the presence of the lattice induces an effective mass for the graviton via a gravitational version of the Higgs mechanism. This allows us to obtain, at leading order in the lattice strength, an analytic expression for the DC conductivity in terms of the size of the lattice at the horizon. In locally critical theories this leads to a power law resistivity that is in agreement with an earlier field theory analysis of Hartnoll and Hofman.
Holographic Quark Matter and Neutron Stars.
Hoyos, Carlos; Jokela, Niko; Rodríguez Fernández, David; Vuorinen, Aleksi
2016-07-15
We use a top-down holographic model for strongly interacting quark matter to study the properties of neutron stars. When the corresponding equation of state (EOS) is matched with state-of-the-art results for dense nuclear matter, we consistently observe a first-order phase transition at densities between 2 and 7 times the nuclear saturation density. Solving the Tolman-Oppenheimer-Volkov equations with the resulting hybrid EOSs, we find maximal stellar masses in excess of two solar masses, albeit somewhat smaller than those obtained with simple extrapolations of the nuclear matter EOSs. Our calculation predicts that no quark matter exists inside neutron stars.
Linearized Holographic Isotropization at Finite Coupling
Atashi, Mahdi; Jafari, Ghadir
2016-01-01
We study holographic isotropization of an anisotropic homogeneous non-Abelian strongly coupled in the presence of Gauss-Bonnet corrections. It was verified before that one can linearize Einstein's equations around the final black hole background and simplify the complicated setup. Using this approach, we study the expectation value of the boundary stress tensor. Although we consider small values of the Gauss-Bonnet coupling constant, it is found that increasing the Gauss-Bonnet coupling leads to significant increasing of the thermalization time. By including higher order corrections, we extend the results to study the effect of the Gauss-Bonnet coupling on the entropy production on the event horizon.
Heavy quarkonium in a holographic basis
Directory of Open Access Journals (Sweden)
Yang Li
2016-07-01
Full Text Available We study the heavy quarkonium within the basis light-front quantization approach. We implement the one-gluon exchange interaction and a confining potential inspired by light-front holography. We adopt the holographic light-front wavefunction (LFWF as our basis function and solve the non-perturbative dynamics by diagonalizing the Hamiltonian matrix. We obtain the mass spectrum for charmonium and bottomonium. With the obtained LFWFs, we also compute the decay constants and the charge form factors for selected eigenstates. The results are compared with the experimental measurements and with other established methods.
Holographic computations of the Quantum Information Metric
Trivella, Andrea
2016-01-01
In this note we show how the Quantum Information Metric can be computed holographically using a perturbative approach. In particular when the deformation of the conformal field theory state is induced by a scalar operator the corresponding bulk configuration reduces to a scalar field perturbatively probing the unperturbed background. We study two concrete examples: a CFT ground state deformed by a primary operator and thermofield double state in $d=2$ deformed by a marginal operator. Finally, we generalize the bulk construction to the case of a multi dimensional parameter space and show that the Quantum Information Metric coincides with the metric of the non-linear sigma model for the corresponding scalar fields.
QCD and a holographic model of hadrons.
Erlich, Joshua; Katz, Emanuel; Son, Dam T; Stephanov, Mikhail A
2005-12-31
We propose a five-dimensional framework for modeling low-energy properties of QCD. In the simplest three parameter model we compute masses, decay rates and couplings of the lightest mesons. The model fits experimental data to within 10%. The framework is a holographic version of the QCD sum rules, motivated by the anti-de Sitter/conformal field theory correspondence. The model naturally incorporates properties of QCD dictated by chiral symmetry, which we demonstrate by deriving the Gell-Mann-Oakes-Renner relationship for the pion mass.
Peptide oligomers for holographic data storage
DEFF Research Database (Denmark)
Berg, Rolf Henrik; Hvilsted, Søren; Ramanujam, P.S.
1996-01-01
SEVERAL classes of organic materials (such as photoanisotropic liquid-crystalline polymers(1-4) and photorefractive polymers(5-7)) are being investigated for the development of media for optical data storage. Here we describe a new family of organic materials-peptide oligomers containing azobenzene...... chromophores-which appear particularly promising for erasable holographic data storage applications. The rationale for our approach is to use the structural properties of peptide-like molecules to impose orientational order on the chromophores, and thereby optimize the optical properties of the resulting...
Simple recipe for holographic Weyl anomaly
Bugini, F
2016-01-01
We propose a recipe - arguably the simplest - to compute the holographic type-B Weyl anomaly for general higher-derivative gravity in asymptotically AdS spacetimes. In 5 and 7 dimensions we identify a suitable basis of curvature invariants that allows to read off easily, without any further computation, the Weyl anomaly coefficients of the dual CFT. We tabulate the contributions from quadratic, cubic and quartic purely algebraic curvature invariants and also from terms involving derivatives of the curvature. We provide few examples, where the anomaly coefficients have been obtained by other means, to illustrate the effectiveness of our prescription.
Holographic quark matter and neutron stars
Hoyos, Carlos; Jokela, Niko; Vuorinen, Aleksi
2016-01-01
We use a top-down holographic model for strongly interacting quark matter to study the properties of neutron stars. When the corresponding Equation of State (EoS) is matched with state-of-the-art results for dense nuclear matter, we consistently observe a first order phase transition at densities between two and seven times the nuclear saturation density. Solving the Tolman-Oppenheimer-Volkov equations with the resulting hybrid EoSs, we find maximal stellar masses in the excess of two solar masses, albeit somewhat smaller than those obtained with simple extrapolations of the nuclear matter EoSs.
A Holographic Dual of the Quantum Inequalities
Levine, Adam R
2016-01-01
In this note, we establish the 2-D Quantum Inequalities - first proved by Flanagan - for all CFTs with a causal holographic dual. Following the treatment of Kelly \\& Wall, we establish that the Boundary Causality Condition in an asymptotic AdS spacetime implies the Quantum Inequalities on the boundary. Our results extend easily to curved spacetime and are stable under deformations of the CFT by relevant operators. We discuss higher dimensional generalizations and possible connections to recent bounds on $a/c$ in 4-D CFTs.
Drag phenomena from holographic massive gravity
Baggioli, Matteo; Brattan, Daniel K.
2017-01-01
We consider the motion of point particles in a strongly coupled field theory with broken translation invariance. We obtain the energy and momentum loss rates and drag coefficients for a class of such particles by solving for the motion of classical strings in holographic massive gravity. At low temperatures compared to the graviton mass the behaviour of the string is controlled by the appearance of an exotic ground state with non-zero entropy at zero temperature. Additionally, we find an upper bound on the diffusion constant for a collection of these particles which is saturated when the mass of the graviton goes to zero.
Drag phenomena from holographic massive gravity
Baggioli, Matteo
2015-01-01
We consider the motion of point particles in a strongly coupled field theory with broken translation invariance. We obtain the energy and momentum loss rates and drag coefficients for a class of such particles by solving for the motion of classical strings in holographic massive gravity. At low temperatures compared to the graviton mass the behaviour of the string is controlled by the appearance of an exotic ground state with non-zero entropy at zero temperature. Additionally we find an upper bound on the diffusion constant for a collection of these particles which is saturated when the mass of the graviton goes to zero.
Optoelectronic implementation of multilayer perceptron and Hopfield neural networks
Domanski, Andrzej W.; Olszewski, Mikolaj K.; Wolinski, Tomasz R.
2004-11-01
In this paper we present an optoelectronic implementation of two networks based on multilayer perceptron and the Hopfield neural network. We propose two different methods to solve a problem of lack of negative optical signals that are necessary for connections between layers of perceptron as well as within the Hopfield network structure. The first method applied for construction of multilayer perceptron was based on division of signals into two channels and next to use both of them independently as positive and negative signals. The second one, applied for implementation of the Hopfield model, was based on adding of constant value for elements of matrix weight. Both methods of compensation of lack negative optical signals were tested experimentally as optoelectronic models of multilayer perceptron and Hopfield neural network. Special configurations of optical fiber cables and liquid crystal multicell plates were used. In conclusion, possible applications of the optoelectronic neural networks are briefly discussed.
History of modern optics ad optoelectronics development in China
Tian, Shouyun
2014-01-01
This book presents a collection of memoir papers on the development of modern and contemporary optics and optoelectronics in China from the 18th to 20th centuries. The papers were written by famous scientists in China, including members of the Chinese Academy of Sciences and the Chinese Academy of Engineering, sharing their experience in different fields of optics and optoelectronics development. This is a unique book in understanding the natural science history of optics and optoelectronics. It gives you the general idea about how the western optical science spread to China in the 17th to 18th century; the cradle of the contemporary optics in China; Birth, development and application of lasers in China; high energy and high power lasers for laser antiballistic missile and laser nuclear fusion; development of Chinese optical communication and optical information storage; laser and infrared optics research for space science; development of Chinese optical instruments, etc.
Practical opto-electronics an illustrated guide for the laboratory
Protopopov, Vladimir
2014-01-01
This book explains how to create opto-electronic systems in a most efficient way, avoiding typical mistakes. It covers light detection techniques, imaging, interferometry, spectroscopy, modulation-demodulation, heterodyning, beam steering, and many other topics common to laboratory applications. The focus is made on self-explanatory figures rather than on words. The book guides the reader through the entire process of creating problem-specific opto-electronic systems, starting from optical source, through beam transportation optical arrangement, to photodetector and data acquisition system. The relevant basics of beam propagation and computer-based raytracing routines are also explained, and sample codes are listed. the book teaches important know-how and practical tricks that are never disclosed in scientific publications. The book can become the reader's personal adviser in the world of opto-electronics and navigator in the ocean of the market of optical components and systems. Succinct, well-illustrate...
High bandgap III-V alloys for high efficiency optoelectronics
Alberi, Kirstin; Mascarenhas, Angelo; Wanlass, Mark
2017-01-10
High bandgap alloys for high efficiency optoelectronics are disclosed. An exemplary optoelectronic device may include a substrate, at least one Al.sub.1-xIn.sub.xP layer, and a step-grade buffer between the substrate and at least one Al.sub.1-xIn.sub.xP layer. The buffer may begin with a layer that is substantially lattice matched to GaAs, and may then incrementally increase the lattice constant in each sequential layer until a predetermined lattice constant of Al.sub.1-xIn.sub.xP is reached.
A class of fascinating optoelectronic materials: Triarylboron compounds
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
Triarylboron compounds are significant optoelectronic materials due to their excellent emissive and electron-transport properties,and could be applied in organic light-emitting diodes as emissive and/or electron-transport layers.Triarylboron compounds have vacant pπ orbital and have received increasing interest as fluoride ion and cyanide ion sensors utilizing specific Lewis acid-base interaction.This review summarizes their structural characteristics,optical properties and applications in chemosensors for anions and optoelectronic devices developed in recent years and discusses the problems and prospects.
Research on optical multistage butterfly interconnection and optoelectronic logic operations
Sun, De-Gui; Wang, Na-Xin; He, Li-Ming; Xu, Mai; Liang, Guo-Dong; Zheng, Jie
We briefly study butterfly interconnection construction and propose an experimental approach to implementing multistage butterfly interconnection networks by using a special interconnection grating with the reflection ladder structure and liquid crystal light valves (LCLVs), and implementing the optical butterfly interconnections and primary optical digital logic operations. With this foundation, we analyse and discuss the features of the approach by computer simulations. In terms of our theoretical analyses, we improve the ring-circuit approach, based on the reflection ladder structure gratings, into a more suitable form based on transmission gratings, and we substitute the LCLVs with optoelectronic switches. Finally we give the experimental results of both the transmission grating and optoelectronic switches.
Magnetic and optoelectronic properties of gold nanocluster-thiophene assembly.
Qin, Wei; Lohrman, Jessica; Ren, Shenqiang
2014-07-07
Nanohybrids consisting of Au nanocluster and polythiophene nanowire assemblies exhibit unique thermal-responsive optical behaviors and charge-transfer controlled magnetic and optoelectronic properties. The ultrasmall Au nanocluster enhanced photoabsorption and conductivity effectively improves the photocurrent of nanohybrid based photovoltaics, leading to an increase of power conversion efficiency by 14 % under AM 1.5 illumination. In addition, nanohybrids exhibit electric field controlled spin resonance and magnetic field sensing behaviors, which open up the potential of charge-transfer complex system where the magnetism and optoelectronics interact.
A reconfigurable optoelectronic interconnect technology for multi-processor networks
Energy Technology Data Exchange (ETDEWEB)
Lu, Y.C.; Cheng, J. [Univ. of New Mexico, Albuquerque, NM (United States). Center for High Technology Materials; Zolper, J.C.; Klem, J. [Sandia National Labs., Albuquerque, NM (United States)
1995-05-01
This paper describes a new optical interconnect architecture and the integrated optoelectronic circuit technology for implementing a parallel, reconfigurable, multiprocessor network. The technology consists of monolithic array`s of optoelectronic switches that integrate vertical-cavity surface-emitting lasers with three-terminal heterojunction phototransistors, which effectively combined the functions of an optical transceiver and an optical spatial routing switch. These switches have demonstrated optical switching at 200 Mb/s, and electrical-to-optical data conversion at > 500 Mb/s, with a small-signal electrical-to-optical modulation bandwidth of {approximately} 4 GHz.
High bandgap III-V alloys for high efficiency optoelectronics
Energy Technology Data Exchange (ETDEWEB)
Alberi, Kirstin; Mascarenhas, Angelo; Wanlass, Mark
2017-01-10
High bandgap alloys for high efficiency optoelectronics are disclosed. An exemplary optoelectronic device may include a substrate, at least one Al.sub.1-xIn.sub.xP layer, and a step-grade buffer between the substrate and at least one Al.sub.1-xIn.sub.xP layer. The buffer may begin with a layer that is substantially lattice matched to GaAs, and may then incrementally increase the lattice constant in each sequential layer until a predetermined lattice constant of Al.sub.1-xIn.sub.xP is reached.
Applications of HTSC films in hybrid optoelectronic devices
Pavuna, Davor
1992-03-01
An overview is given of potential applications of high-Tc superconductors (HTSC) in the context of hybrid optoelectronic technology. The main requirements are described for the in situ growth of epitaxial YBa2Cu3O(7-delta) (YBCO) films on SrTiO3 and discuss the properties of YBCO layers grown on Si and GaAs substrates with intermediate, conducting indium-tin-oxide buffer layers. The performances of the microbridge and the meander type of HTSC bolometer are compared, and several concepts are discussed that may become relevant for future hybrid optoelectronic technology.
Optoelectronic devices, plasmonics, and photonics with topological insulators
Politano, Antonio; Viti, Leonardo; Vitiello, Miriam S.
2017-03-01
Topological insulators are innovative materials with semiconducting bulk together with surface states forming a Dirac cone, which ensure metallic conduction in the surface plane. Therefore, topological insulators represent an ideal platform for optoelectronics and photonics. The recent progress of science and technology based on topological insulators enables the exploitation of their huge application capabilities. Here, we review the recent achievements of optoelectronics, photonics, and plasmonics with topological insulators. Plasmonic devices and photodetectors based on topological insulators in a wide energy range, from terahertz to the ultraviolet, promise outstanding impact. Furthermore, the peculiarities, the range of applications, and the challenges of the emerging fields of topological photonics and thermo-plasmonics are discussed.
An adaptive holographic implementation of a neural network
Downie, John D.; Hine, Butler P., III; Reid, Max B.
1990-01-01
A holographic implementation for neural networks is proposed and demonstrated as an alternative to the optical matrix-vector multiplier architecture. In comparison, the holographic architecture makes more efficient use of the system space-bandwidth product for certain types of neural networks. The principal network component is a thermoplastic hologram, used to provide both interconnection weights and beam direction. Given the updatable nature of this type of hologram, adaptivity or network learning is possible in the optical system. Two networks with fixed weights are experimentally implemented and verified, and for one of these examples the advantage of the holographic implementation with respect to the matrix-vector processor is demonstrated.
Inflation via logarithmic entropy-corrected holographic dark energy model
Energy Technology Data Exchange (ETDEWEB)
Darabi, F.; Felegary, F. [Azarbaijan Shahid Madani University, Department of Physics, Tabriz (Iran, Islamic Republic of); Setare, M.R. [University of Kurdistan, Department of Science, Bijar (Iran, Islamic Republic of)
2016-12-15
We study the inflation in terms of the logarithmic entropy-corrected holographic dark energy (LECHDE) model with future event horizon, particle horizon, and Hubble horizon cut-offs, and we compare the results with those obtained in the study of inflation by the holographic dark energy HDE model. In comparison, the spectrum of primordial scalar power spectrum in the LECHDE model becomes redder than the spectrum in the HDE model. Moreover, the consistency with the observational data in the LECHDE model of inflation constrains the reheating temperature and Hubble parameter by one parameter of holographic dark energy and two new parameters of logarithmic corrections. (orig.)
Inflation via logarithmic entropy-corrected holographic dark energy model
Darabi, F; Setare, M R
2016-01-01
We study the inflation via logarithmic entropy-corrected holographic dark energy LECHDE model with future event horizon, particle horizon and Hubble horizon cut-offs, and compare the results with those of obtained in the study of inflation by holographic dark energy HDE model. In comparison, the spectrum of primordial scalar power spectrum in the LECHDE model becomes redder than the spectrum in HDE model. Moreover, the consistency with the observational data in LECHDE model of inflation, constrains the reheating temperature and Hubble parameter by one parameter of holographic dark energy and two new parameters of logarithmic corrections.
Complexified boost invariance and holographic heavy ion collisions
Gubser, Steven S
2015-01-01
At strong coupling holographic studies have shown that heavy ion collisions do not obey normal boost invariance. Here we study a modified boost invariance through a complex shift in time, and show that this leads to surprisingly good agreement with numerical holographic computations. When including perturbations the agreement becomes even better, both in the hydrodynamic and the far-from-equilibrium regime. One of the main advantages is an analytic formulation of the stress-energy tensor of the longitudinal dynamics of holographic heavy ion collisions.
New model for holographic storage by simultaneous angular multiplexing
Ibarra, J. C.; Urzua, D.; Olivares-Peréz, A.; Ortiz-Gutierrez, M.
2006-05-01
We describe a technique for holographic storage by simultaneous angular multiplexing to obtain a large-scale holographic memory. We recorded 72 objects at the same time in one point on holographic plate PFG-03M from Slavich Co., using a He-Ne laser (λ = 633 nm). Each object is placed on a circular photographic transparency, separate 0.94 degree each one. The technique allows us simultaneous reconstruction of the 72 images without cross-talk. The diffraction efficiency obtained at order one is 6%. Experimental results are shown.
Entanglement between Two Interacting CFTs and Generalized Holographic Entanglement Entropy
Mollabashi, Ali; Takayanagi, Tadashi
2014-01-01
In this paper we discuss behaviors of entanglement entropy between two interacting CFTs and its holographic interpretation using the AdS/CFT correspondence. We explicitly perform analytical calculations of entanglement entropy between two free scalar field theories which are interacting with each other in both static and time-dependent ways. We also conjecture a holographic calculation of entanglement entropy between two interacting $\\mathcal{N}=4$ super Yang-Mills theories by introducing a minimal surface in the S$^5$ direction, instead of the AdS$_5$ direction. This offers a possible generalization of holographic entanglement entropy.
Entanglement between two interacting CFTs and generalized holographic entanglement entropy
Mollabashi, Ali; Shiba, Noburo; Takayanagi, Tadashi
2014-04-01
In this paper we discuss behaviors of entanglement entropy between two interacting CFTs and its holographic interpretation using the AdS/CFT correspondence. We explicitly perform analytical calculations of entanglement entropy between two free scalar field theories which are interacting with each other in both static and time-dependent ways. We also conjecture a holographic calculation of entanglement entropy between two interacting = 4 super Yang-Mills theories by introducing a minimal surface in the S5 direction, instead of the AdS5 direction. This offers a possible generalization of holographic entanglement entropy.
Entanglement between two interacting CFTs and generalized holographic entanglement entropy
Energy Technology Data Exchange (ETDEWEB)
Mollabashi, Ali [School of physics, Institute for Research in Fundamental Sciences (IPM),Tehran (Iran, Islamic Republic of); Yukawa Institute for Theoretical Physics (YITP),Kyoto University, Kyoto 606-8502 (Japan); Shiba, Noburo [Yukawa Institute for Theoretical Physics (YITP),Kyoto University, Kyoto 606-8502 (Japan); Takayanagi, Tadashi [Yukawa Institute for Theoretical Physics (YITP),Kyoto University, Kyoto 606-8502 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU),University of Tokyo, Kashiwa, Chiba 277-8582 (Japan)
2014-04-30
In this paper we discuss behaviors of entanglement entropy between two interacting CFTs and its holographic interpretation using the AdS/CFT correspondence. We explicitly perform analytical calculations of entanglement entropy between two free scalar field theories which are interacting with each other in both static and time-dependent ways. We also conjecture a holographic calculation of entanglement entropy between two interacting N=4 super Yang-Mills theories by introducing a minimal surface in the S{sup 5} direction, instead of the AdS{sub 5} direction. This offers a possible generalization of holographic entanglement entropy.
Generation of spatial Bessel beams using holographic metasurface.
Cai, Ben Geng; Li, Yun Bo; Jiang, Wei Xiang; Cheng, Qiang; Cui, Tie Jun
2015-03-23
We propose to use backward radiations of leaky waves supported by a holographic metasurface to produce spatial Bessel beams in the microwave frequency regime. The holographic metasurface consists of a grounded dielectric slab and a series of metal patches. By changing the size of metal patches, the surface-impedance distribution of the holographic metasurface can be modulated, and hence the radiation properties of the leaky waves can be designed to realize Bessel beams. Both numerical simulations and experiments verify the features of spatial Bessel beams, which may be useful in imaging applications or wireless power transmissions with the dynamic focal-depth controls.
Lifshitz holographic superconductor in Hořava–Lifshitz gravity
Energy Technology Data Exchange (ETDEWEB)
Luo, Cheng-Jian, E-mail: rocengeng@hotmail.com [Department of Physics, Nanchang University, Nanchang, 330031 (China); Center for Relativistic Astrophysics and High Energy Physics, Nanchang University, Nanchang 330031 (China); Kuang, Xiao-Mei, E-mail: xmeikuang@gmail.com [Instituto de Física, Pontificia Universidad Católica de Valparaíso, Casilla 4059, Valparaíso (Chile); Shu, Fu-Wen, E-mail: shufuwen@ncu.edu.cn [Department of Physics, Nanchang University, Nanchang, 330031 (China); Center for Relativistic Astrophysics and High Energy Physics, Nanchang University, Nanchang 330031 (China)
2016-08-10
We study the holographic phase transition of superconductor dual to a Lifshitz black brane probed by an anisotropic scalar field in the probe limit in Hořava–Lifshitz gravity. With the use of numerical and analytical method, we investigate how the critical temperature of the condensation is affected by the Lifshitz exponent z, α-correction term in the action as well as the dimensions of the gravity. We also numerically explore the condensation of the dual operator and optical conductivity of the holographic system. Various interesting properties of the holographic condensation affected by the parameters of model are discussed.
Lifshitz holographic superconductor in Horava-Lifshitz gravity
Luo, Cheng-Jian; Shu, Fu-Wen
2016-01-01
We study the holographic phase transition of superconductor dual to a Lifshitz black brane probed by an anisotropic scalar field in the probe limit in Ho\\u{r}ava-Lifshitz gravity. With the use of numerical and analytical method, we investigate how the critical temperature of the condensation is affected by the Lifshitz exponent $z$, $\\alpha-$correction term in the action as well as the dimensions of the gravity. We also numerically explore the condensation of the dual operator and optical conductivity of the holographic system. Various interesting properties of the holographic condensation affected by the parameters of model are discussed.
Recent progress in backreacted bottom-up holographic QCD
Energy Technology Data Exchange (ETDEWEB)
Järvinen, Matti [Laboratoire de Physique Théorique, École Normale Supérieure, 24 rue Lhomond, 75231 Paris Cedex 05 (France)
2016-01-22
Recent progress in constructing holographic models for QCD is discussed, concentrating on the bottom-up models which implement holographically the renormalization group flow of QCD. The dynamics of gluons can be modeled by using a string-inspired model termed improved holographic QCD, and flavor can be added by introducing space filling branes in this model. The flavor fully backreacts to the glue in the Veneziano limit, giving rise to a class of models which are called V-QCD. The phase diagrams and spectra of V-QCD are in good agreement with results for QCD obtained by other methods.
Solitonic approach to holographic nuclear physics
Baldino, Salvatore; Bolognesi, Stefano; Gudnason, Sven Bjarke; Koksal, Deniz
2017-08-01
We discuss nuclear physics in the Sakai-Sugimoto model in the limit of a large number Nc of colors and large 't Hooft coupling λ . In this limit the individual baryons are described by classical solitons whose size is much smaller than the typical distance at which they settle in a nuclear bound state. We can thus use the linear approximation outside the instanton cores to compute the interaction potential. We find the classical geometry of nuclear bound states for baryon number up to 8. One of the interesting features that we find is that holographic nuclear physics provides a natural description for lightly bound states when λ is large. For the case of two nuclei, we also find the topology and metric of the manifold of zero modes and, quantizing it, we find that the ground state can be identified with the deuteron state. We discuss the relations with other methods in the literature used to study Skyrmions and holographic nuclear physics. We discuss 1 /Nc and 1 /λ corrections and the challenges to overcome to reach the phenomenological values to fit with real QCD.
A Holographic Approach to Spacetime Entanglement
Wien, Jason
2014-01-01
Recently it has been proposed that the Bekenstein-Hawking formula for the entropy of spacetime horizons has a larger significance as the leading contribution to the entanglement entropy of general spacetime regions, in the underlying quantum theory [2]. This `spacetime entanglement conjecture' has a holographic realization that equates the entropy formula evaluated on an arbitrary space-like co-dimension two surface with the differential entropy of a particular family of co-dimension two regions on the boundary. The differential entropy can be thought of as a directional derivative of entanglement entropy along a family of surfaces. This holographic relation was first studied in [3] and extended in [4], and it has been proven to hold in Einstein gravity for bulk surfaces with planar symmetry (as well as for certain higher curvature theories) in [4]. In this essay, we review this proof and provide explicit examples of how to build the appropriate family of boundary intervals for a given bulk curve. Conversely,...
Holographic quenches towards a Lifshitz point
Camilo, Giancarlo; Abdalla, Elcio
2015-01-01
We use the holographic duality to study quantum quenches of a strongly coupled CFT that drive the theory towards a non-relativistic fixed point with Lifshitz scaling. We consider the case of a Lifshitz dynamical exponent $z$ close to unity, where the non-relativistic field theory can be understood as a specific deformation of the corresponding CFT and, hence, the standard holographic dictionary can be applied. On the gravity side this amounts to finding a dynamical bulk solution which interpolates between AdS and Lishitz spacetimes as time evolves. We show that an asymptotically Lifshitz black hole is always formed in the final state. This indicates that it is impossible to reach the vacuum state of the Lifshitz theory from the CFT vacuum as a result of the proposed quenching mechanism. The nonequilibrium dynamics following the breaking of the relativistic scaling symmetry is also probed using both local and non-local observables. In particular, we conclude that the equilibration process happens in a top-down...
Holographic dark energy with cosmological constant
Hu, Yazhou; Li, Miao; Li, Nan; Zhang, Zhenhui
2015-08-01
Inspired by the multiverse scenario, we study a heterotic dark energy model in which there are two parts, the first being the cosmological constant and the second being the holographic dark energy, thus this model is named the ΛHDE model. By studying the ΛHDE model theoretically, we find that the parameters d and Ωhde are divided into a few domains in which the fate of the universe is quite different. We investigate dynamical behaviors of this model, and especially the future evolution of the universe. We perform fitting analysis on the cosmological parameters in the ΛHDE model by using the recent observational data. We find the model yields χ2min=426.27 when constrained by Planck+SNLS3+BAO+HST, comparable to the results of the HDE model (428.20) and the concordant ΛCDM model (431.35). At 68.3% CL, we obtain -0.07<ΩΛ0<0.68 and correspondingly 0.04<Ωhde0<0.79, implying at present there is considerable degeneracy between the holographic dark energy and cosmological constant components in the ΛHDE model.
Holographic Photon Production in Heavy Ion Collisions
Iatrakis, Ioannis; Shen, Chun; Yang, Di-Lun
2016-01-01
The thermal-photon emission from strongly coupled gauge theories at finite temperature is calculated using holographic models for QCD in the Veneziano limit (V-QCD). The emission rates are then embedded in hydrodynamic simulations combined with prompt photons from hard scattering and the thermal photons from hadron gas to analyze the spectra and anisotropic flow of direct photons at RHIC and LHC. The results from different sources responsible for the thermal photons in QGP including the weakly coupled QGP (wQGP) from perturbative calculations, strongly coupled $\\mathcal{N}=4$ super Yang-Mills (SYM) plasma (as a benchmark for reference), and Gubser's phenomenological holographic model are then compared. It is found that the direct-photon spectra are enhanced in the strongly coupled scenario compared with the ones in the wQGP, especially at high momenta. Moreover, by using IP-glassma initial states, both the elliptic flow and triangular flow of direct photons are amplified at high momenta for V-QCD and the SYM ...
Riccati equations for holographic 2-point functions
Papadimitriou, Ioannis; Taliotis, Anastasios
2014-04-01
Any second order homogeneous linear ordinary differential equation can be transformed into a first order non-linear Riccati equation. We argue that the Riccati form of the linearized fluctuation equations that determine the holographic 2-point functions simplifies considerably the numerical computation of such 2-point functions and of the corresponding transport coefficients by computing directly the response functions, eliminating the arbitrary source from the start. Moreover, it provides a neat criterion for the infrared regularity of the fluctuations. In particular, it is shown that the infrared regularity conditions for scalar and tensor fluctuations coincide, and hence they are either both regular or both singular. We demonstrate our numerical recipe based on the Riccati equations by computing the holographic 2-point functions for the stress tensor and a scalar operator in a number of asymptotically anti de Sitter backgrounds of bottom up scalar-gravity models. Analytical results are obtained for the 2-point function of the transverse traceless part of the stress tensor in two confining geometries, including a geometry that belongs to the class of IHQCD. We find that in this background the spin-2 spectrum is linear and, as expected, the position space 2-point function decays exponentially at large distances at a rate proportional to the confinement scale.
Free energy of a Lovelock holographic superconductor
Aranguiz, Ligeia
2014-01-01
We study black hole solutions in Lanczos-Lovelock AdS gravity in d+1 dimensions coupled to nonlinear electrodynamics and a Stueckelberg scalar field. This class of theories with [d/2] gravitational coupling constants and two arbitrary functions that govern the matter interaction is used in the context of gauge/gravity duality to describe a high-temperature superconductor in d dimensions. We regularize the gravitational action and find the finite conserved quantities for a planar black hole with scalar hair. Then we derive the quantum statistical relation in the Euclidean sector of the theory, and obtain the exact formula for the free energy of the superconductor in the holographic quantum field theory. Our result is exact, analytic and it includes the effects of back reaction of the gravitational field. We further discuss on how this formula could be used to analyze second order phase transitions through the discontinuities of the free energy, and classify holographic superconductors in terms of the parameter...
Holographic free energy and thermodynamic geometry
Energy Technology Data Exchange (ETDEWEB)
Ghorai, Debabrata [S.N. Bose National Centre for Basic Sciences, Kolkata (India); Gangopadhyay, Sunandan [Indian Institute of Science Education and Research, Kolkata, Nadia (India); West Bengal State University, Department of Physics, Barasat (India); Inter University Centre for Astronomy and Astrophysics, Pune (India)
2016-12-15
We obtain the free energy and thermodynamic geometry of holographic superconductors in 2 + 1 dimensions. The gravitational theory in the bulk dual to this 2 + 1-dimensional strongly coupled theory lives in the 3 + 1 dimensions and is that of a charged AdS black hole together with a massive charged scalar field. The matching method is applied to obtain the nature of the fields near the horizon using which the holographic free energy is computed through the gauge/gravity duality. The critical temperature is obtained for a set of values of the matching point of the near horizon and the boundary behaviour of the fields in the probe limit approximation which neglects the back reaction of the matter fields on the background spacetime geometry. The thermodynamic geometry is then computed from the free energy of the boundary theory. From the divergence of the thermodynamic scalar curvature, the critical temperature is obtained once again. We then compare this result for the critical temperature with that obtained from the matching method. (orig.)
Moduli Spaces of Cold Holographic Matter
Ammon, Martin; Kim, Keun-Young; Laia, João; O'Bannon, Andy
2012-01-01
We use holography to study (3+1)-dimensional N=4 supersymmetric Yang-Mills theory with gauge group SU(Nc), in the large-Nc and large-coupling limits, coupled to a single massless (n+1)-dimensional hypermultiplet in the fundamental representation of SU(Nc), with n=3,2,1. In particular, we study zero-temperature states with a nonzero baryon number charge density, which we call holographic matter. We demonstrate that a moduli space of such states exists in these theories, specifically a Higgs branch parameterized by the expectation values of scalar operators bilinear in the hypermultiplet scalars. At a generic point on the Higgs branch, the R-symmetry and gauge group are spontaneously broken to subgroups. Our holographic calculation consists of introducing a single probe Dp-brane into AdS5 times S^5, with p=2n+1=7,5,3, introducing an electric flux of the Dp-brane worldvolume U(1) gauge field, and then obtaining explicit solutions for the worldvolume fields dual to the scalar operators that parameterize the Higgs...
Gravitation, holographic principle, and extra dimensions
Caimmi, R
2016-01-01
Within the context of Newton's theory of gravitation, restricted to point-like test particles and central bodies, stable circular orbits in ordinary space are related to stable circular paths on a massless, unmovable, undeformable vortex-like surface, under the action of a tidal gravitational field along the symmetry axis. An interpretation is made in the light of a holographic principle, in the sense that motions in ordinary space are connected with motions on a selected surface and vice versa. Then ordinary space is conceived as a 3-hypersurface bounding a $n$-hypervolume where gravitation takes origin, within a $n$-hyperspace. The extension of the holographic principle to extra dimensions implies the existence of a minimum distance where test particles may still be considered as distinct from the central body. Below that threshold, it is inferred test particles lose theirs individuality and "glue" to the central body via unification of the four known interactions and, in addition, (i) particles can no long...
Riccati equations for holographic 2-point functions
Energy Technology Data Exchange (ETDEWEB)
Papadimitriou, Ioannis [Instituto de Física Teórica UAM/CSIC, Universidad Autónoma de Madrid,Madrid 28049 (Spain); Taliotis, Anastasios [Theoretische Natuurkunde, Vrije Universiteit Brussel,and International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium)
2014-04-30
Any second order homogeneous linear ordinary differential equation can be transformed into a first order non-linear Riccati equation. We argue that the Riccati form of the linearized fluctuation equations that determine the holographic 2-point functions simplifies considerably the numerical computation of such 2-point functions and of the corresponding transport coefficients by computing directly the response functions, eliminating the arbitrary source from the start. Moreover, it provides a neat criterion for the infrared regularity of the fluctuations. In particular, it is shown that the infrared regularity conditions for scalar and tensor fluctuations coincide, and hence they are either both regular or both singular. We demonstrate our numerical recipe based on the Riccati equations by computing the holographic 2-point functions for the stress tensor and a scalar operator in a number of asymptotically anti de Sitter backgrounds of bottom up scalar-gravity models. Analytical results are obtained for the 2-point function of the transverse traceless part of the stress tensor in two confining geometries, including a geometry that belongs to the class of IHQCD. We find that in this background the spin-2 spectrum is linear and, as expected, the position space 2-point function decays exponentially at large distances at a rate proportional to the confinement scale.
Setting up of holographic optical tweezer arrays
Gupta, Deepak K.; Tata, B. V. R.; Ravindran, T. R.
2017-05-01
Optical tweezers use tightly focused laser beams to hold and move microscopic objects in a solvent. However, many applications require simultaneous control over multitude of particles, positioning them in 3D space at desired locations with desired symmetry, which is made possible by the use of holographic optical tweezers using the technique of beam shaping and holography. We have designed and developed a holographic optical tweezer set-up using a phase only liquid crystal, reflective spatial light modulator. We employ the technique of phase modulation to modulate the phase of the beam by generating holograms using Random Superposition (RS) and weighted Gerchberg Saxton algorithm (WGS) algorithm for generating desired patterns of light at the trapping plane. A 4×4 array of beams with square symmetry was generated using WGS algorithm and trapped polystyrene particles of size 1.2 micron in a 4×4 two dimensional array. There were uniformity issues among the trap intensities, as we move away from the zeroth order spot. This was corrected by taking into account diffraction effects due to the pixelated nature of SLM modulating the intensity of the trap spots and the ghost order suppression by spatial disorder.
Random holographic "large worlds" with emergent dimensions
Trugenberger, Carlo A.
2016-11-01
I propose a random network model governed by a Gaussian weight corresponding to Ising link antiferromagnetism as a model for emergent quantum space-time. In this model, discrete space is fundamental, not a regularization; its spectral dimension ds is not a model input but is, rather, completely determined by the antiferromagnetic coupling constant. Perturbative terms suppressing triangles and favoring squares lead to locally Euclidean ground states that are Ricci flat "large worlds" with power-law extension. I then consider the quenched graphs of lowest energy for ds=2 and ds=3 , and I show how quenching leads to the spontaneous emergence of embedding spaces of Hausdorff dimension dH=4 and dH=5 , respectively. One of the additional, spontaneous dimensions can be interpreted as time, causality being an emergent property that arises in the large N limit (with N the number of vertices). For ds=2 , the quenched graphs constitute a discrete version of a 5D-space-filling surface with a number of fundamental degrees of freedom scaling like N2 /5, a graph version of the holographic principle. These holographic degrees of freedom can be identified with the squares of the quenched graphs, which, being triangle-free, are the fundamental area (or loop) quanta.
AdS$_2$ Holographic Dictionary
Cvetič, Mirjam
2016-01-01
We construct the holographic dictionary for both running and constant dilaton solutions of the 2D Einstein-Maxwell-Dilaton theory obtained by a circle reduction from 3D gravity with negative cosmological constant. This specific model ensures that the dual theory has a well defined ultraviolet completion in terms of a 2D CFT, but our results apply qualitatively to a wider class of 2D dilaton gravity theories. For each type of solutions we perform holographic renormalization, compute the exact renormalized one-point functions in the presence of arbitrary sources, and derive the asymptotic symmetries and conserved charges. In both cases we find that the scalar operator dual to the dilaton plays a crucial role in the description of the dynamics. Its source gives rise to a matter conformal anomaly for the running dilaton solutions, while its expectation value is the only non trivial observable for constant dilaton solutions. The role of this operator has been largely overlooked in the literature. We further show t...
Holographic Dynamics from Multiscale Entanglement Renormalization Ansatz
Chua, Victor; Tiwari, Apoorv; Ryu, Shinsei
2016-01-01
The Multiscale Entanglement Renormalization Ansatz (MERA) is a tensor network based variational ansatz that is capable of capturing many of the key physical properties of strongly correlated ground states such as criticality and topological order. MERA also shares many deep relationships with the AdS/CFT (gauge-gravity) correspondence by realizing a UV complete holographic duality within the tensor networks framework. Motivated by this, we have re-purposed the MERA tensor network as an analysis tool to study the real-time evolution of the 1D transverse Ising model in its low energy excited state sector. We performed this analysis by allowing the ancilla qubits of the MERA tensor network to acquire quantum fluctuations, which yields a unitary transform between the physical (boundary) and ancilla qubit (bulk) Hilbert spaces. This then defines a reversible quantum circuit which is used as a `holographic transform' to study excited states and their real-time dynamics from the point of the bulk ancillae. In the ga...
2012-10-30
... COMMISSION Certain Optoelectronic Devices for Fiber Optic Communications, Components Thereof, and Products... Singapore; and Avago Technologies U.S. Inc. of San Jose, California. Letters supplementing the complaint... the United States after importation of certain optoelectronic devices for fiber optic...
Parallel optical interconnects - Implementation of optoelectronics in multiprocessor architectures
Frietman, E. E. E.; Dekker, L.; van Nifterick, W.; Jongeling, T. J. M.
1990-03-01
Optoelectronic logic element circuitries are described which can be used for the implementation of a wide variety of interconnection schemes. Particular attention is given to the design, construction, and application of an electrooptic communication system (EOCS) using dedicated free space multiple data distributors and integrated optically writable input buffer arrays with fully parallel access. Some experimental results obtained on the complete EOCS are presented.
Opto-electronic properties of charged conjugated molecules
Fratiloiu, S.
2007-01-01
The aim of this thesis is to provide fundamental insight into the nature and opto-electronic properties of charge carriers on conjugated oligomers and polymers. Electronic structure, optical absorption properties and distribution of charge carriers along the chains of different conjugated materials
Advances in wide bandgap SiC for optoelectronics
DEFF Research Database (Denmark)
Ou, Haiyan; Ou, Yiyu; Argyraki, Aikaterini
2014-01-01
Silicon carbide (SiC) has played a key role in power electronics thanks to its unique physical properties like wide bandgap, high breakdown field, etc. During the past decade, SiC is also becoming more and more active in optoelectronics thanks to the progress in materials growth and nanofabrication...
Optoelectronic Correlator Architecture for Shift Invariant Target Recognition
Monjur, Mehjabin S; Tripathi, Renu; Donoghue, John; Shahriar, M S
2013-01-01
In this paper, we present theoretical details and the underlying architecture of a hybrid optoelectronic correlator that correlates images using SLMs, detectors and VLSI chips. The proposed architecture bypasses the nonlinear material such as photorefractive polymer film by using detectors instead, and the phase information is yet conserved by the interference of plane waves with the images.
Intersatellite communications optoelectronics research at the Goddard Space Flight Center
Krainak, Michael A.
1992-01-01
A review is presented of current optoelectronics research and development at the NASA Goddard Space Flight Center for high-power, high-bandwidth laser transmitters; high-bandwidth, high-sensitivity optical receivers; pointing, acquisition, and tracking components; and experimental and theoretical system modeling at the NASA Goddard Space Flight Center. Program hardware and space flight opportunities are presented.
Simultaneous Thermoelectric and Optoelectronic Characterization of Individual Nanowires.
Léonard, François; Song, Erdong; Li, Qiming; Swartzentruber, Brian; Martinez, Julio A; Wang, George T
2015-12-01
Semiconducting nanowires have been explored for a number of applications in optoelectronics such as photodetectors and solar cells. Currently, there is ample interest in identifying the mechanisms that lead to photoresponse in nanowires in order to improve and optimize performance. However, distinguishing among the different mechanisms, including photovoltaic, photothermoelectric, photoemission, bolometric, and photoconductive, is often difficult using purely optoelectronic measurements. In this work, we present an approach for performing combined and simultaneous thermoelectric and optoelectronic measurements on the same individual nanowire. We apply the approach to GaN/AlGaN core/shell and GaN/AlGaN/GaN core/shell/shell nanowires and demonstrate the photothermoelectric nature of the photocurrent observed at the electrical contacts at zero bias, for above- and below-bandgap illumination. Furthermore, the approach allows for the experimental determination of the temperature rise due to laser illumination, which is often obtained indirectly through modeling. We also show that under bias, both above- and below-bandgap illumination leads to a photoresponse in the channel with signatures of persistent photoconductivity due to photogating. Finally, we reveal the concomitant presence of photothermoelectric and photogating phenomena at the contacts in scanning photocurrent microscopy under bias by using their different temporal response. Our approach is applicable to a broad range of nanomaterials to elucidate their fundamental optoelectronic and thermoelectric properties.
Magnetometer Based on the Opto-Electronic Oscillator
Matsko, Andrey B.; Strekalov, Dmitry; Maleki, Lute
2005-01-01
We theoretically propose and discuss properties of two schemes of an all-optical self-oscillating magnetometer based on an opto-electronic oscillator stabilized with an atomic vapor cell. Proof of the principle DC magnetic field measurements characterized with 2 x 10(exp -7) G sensitivity and 1 - 1000 mG dynamic range in one of the schemes are demonstrated.
New Results with the Opto-Electronic Oscillators (OEO)
Yao, S.; Maleki, L.
1996-01-01
A new class of oscillators based on photonic devices is presented. These opto-electronic oscillators (OEOs) generate microwave oscillation by converting continuous energy from a light source using a feedback circuit which includes a delay element, an electro-optic switch, and a photodetctor.
Stabilizing an optoelectronic microwave oscillator with photonic filters
Strekalov, D.; Aveline, D.; Yu, N.; Thompson, R.; Matsko, A. B.; Maleki, L.
2003-01-01
This paper compares methods of active stabilization of an optoelectronic microwave oscillator (OEO) based on insertion of a source of optical group delay into an OEO loop. The performance of an OEO stabilized with either a high- optical cavity or an atomic cell is analyzed. We show that the elements play a role of narrow-band microwave filters improving an OEO stability.
Thirty Gigahertz Optoelectronic Mixing in Chemical Vapor Deposited Graphene.
Montanaro, Alberto; Mzali, Sana; Mazellier, Jean-Paul; Bezencenet, Odile; Larat, Christian; Molin, Stephanie; Morvan, Loïc; Legagneux, Pierre; Dolfi, Daniel; Dlubak, Bruno; Seneor, Pierre; Martin, Marie-Blandine; Hofmann, Stephan; Robertson, John; Centeno, Alba; Zurutuza, Amaia
2016-05-11
The remarkable properties of graphene, such as broadband optical absorption, high carrier mobility, and short photogenerated carrier lifetime, are particularly attractive for high-frequency optoelectronic devices operating at 1.55 μm telecom wavelength. Moreover, the possibility to transfer graphene on a silicon substrate using a complementary metal-oxide-semiconductor-compatible process opens the ability to integrate electronics and optics on a single cost-effective chip. Here, we report an optoelectronic mixer based on chemical vapor-deposited graphene transferred on an oxidized silicon substrate. Our device consists in a coplanar waveguide that integrates a graphene channel, passivated with an atomic layer-deposited Al2O3 film. With this new structure, 30 GHz optoelectronic mixing in commercially available graphene is demonstrated for the first time. In particular, using a 30 GHz intensity-modulated optical signal and a 29.9 GHz electrical signal, we show frequency downconversion to 100 MHz. These results open promising perspectives in the domain of optoelectronics for radar and radio-communication systems.
Heal the world: Avoiding the cosmic doomsday in the holographic dark energy model
Energy Technology Data Exchange (ETDEWEB)
Zhang Xin, E-mail: zhangxin@mail.neu.edu.c [Department of Physics, College of Sciences, Northeastern University, Shenyang 110004 (China); Kavli Institute for Theoretical Physics China, Chinese Academy of Sciences, Beijing 100080 (China)
2010-01-18
The current observational data imply that the universe would end with a cosmic doomsday in the holographic dark energy model. However, unfortunately, the big-rip singularity will ruin the theoretical foundation of the holographic dark energy scenario. To rescue the holographic scenario of dark energy, we employ the braneworld cosmology and incorporate the extra-dimension effects into the holographic theory of dark energy. We find that such a mend could erase the big-rip singularity and leads to a de Sitter finale for the holographic cosmos. Therefore, in the holographic dark energy model, the extra-dimension recipe could heal the world.
Heal the world: Avoiding the cosmic doomsday in the holographic dark energy model
Zhang, Xin
2009-01-01
The current observational data imply that the universe would end with a cosmic doomsday in the holographic dark energy model. However, unfortunately, the big-rip singularity will ruin the theoretical foundation of the holographic dark energy scenario. To rescue the holographic scenario of dark energy, we employ the braneworld cosmology and incorporate the extra-dimension effects into the holographic theory of dark energy. We find that such a mend could erase the big-rip singularity and leads to a de Sitter finale for the holographic cosmos. Therefore, in the holographic dark energy model, the extra-dimension recipe could heal the world.
Exploring Neural Cell Dynamics with Digital Holographic Microscopy
Marquet, Pierre
2013-04-21
In this talk, I will present how digital holographic microscopy, as a powerful quantitative phase technique, can non-invasively measure cell dynamics and especially resolve local neuronal network activity through simultaneous multiple site optical recording.
3D Holographic Technology and Its Educational Potential
Lee, Hyangsook
2013-01-01
This article discusses a number of significant developments in 3D holographic technology, its potential to revolutionize aspects of teaching and learning, and challenges of implementing the technology in educational settings.
A holographic perspective on phonons and pseudo-phonons
Amoretti, Andrea; Argurio, Riccardo; Musso, Daniele; Zayas, Leopoldo A Pando
2016-01-01
We analyze the concomitant spontaneous breaking of translation and conformal symmetries by introducing in a CFT a complex scalar operator that acquires a spatially dependent expectation value. The model, inspired by the holographic Q-lattice, provides a privileged setup to study the emergence of phonons from a spontaneous translational symmetry breaking in a conformal field theory and offers valuable hints for the treatment of phonons in QFT at large. We first analyze the Ward identity structure by means of standard QFT techniques, considering both spontaneous and explicit symmetry breaking. Next, by implementing holographic renormalization, we show that the same set of Ward identities holds in the holographic Q-lattice. Eventually, relying on the holographic and QFT results, we study the correlators realizing the symmetry breaking pattern and how they encode information about the low-energy spectrum.
Fluctuations of spacetime and holographic noise in atomic interferometry
Göklü, Ertan
2009-01-01
Space--time can be understood as some kind of space--time foam of fluctuating bubbles or loops which are expected to be an outcome of a theory of quantum gravity. One recently discussed model for this kind of space--time fluctuations is the holographic principle which allows to deduce the structure of these fluctuations. We review and discuss two scenarios which rely on the holographic principle leading to holographic noise. One scenario leads to fluctuations of the space--time metric affecting the dynamics of quantum systems: (i) an apparent violation of the equivalence principle, (ii) a modification of the spreading of wave packets, and (iii) a loss of quantum coherence. All these effects can be tested with cold atoms. These tests would supplement measurements of a so called ``mystery noise'' at the gravitational wave detector GEO600 which was recently speculated to have its origin in holographic noise.
Quantitative measurement of holographic image quality using Adobe Photoshop
Wesly, E.
2013-02-01
Measurement of the characteristics of image holograms in regards to diffraction efficiency and signal to noise ratio are demonstrated, using readily available digital cameras and image editing software. Illustrations and case studies, using currently available holographic recording materials, are presented.
Imaging and Measuring Electron Beam Dose Distributions Using Holographic Interferometry
DEFF Research Database (Denmark)
Miller, Arne; McLaughlin, W. L.
1975-01-01
Holographic interferometry was used to image and measure ionizing radiation depth-dose and isodose distributions in transparent liquids. Both broad and narrowly collimated electron beams from accelerators (2–10 MeV) provided short irradiation times of 30 ns to 0.6 s. Holographic images and measur......Holographic interferometry was used to image and measure ionizing radiation depth-dose and isodose distributions in transparent liquids. Both broad and narrowly collimated electron beams from accelerators (2–10 MeV) provided short irradiation times of 30 ns to 0.6 s. Holographic images...... and measurements of absorbed dose distributions were achieved in liquids of various densities and thermal properties and in water layers thinner than the electron range and with backings of materials of various densities and atomic numbers. The lowest detectable dose in some liquids was of the order of a few k...
Holographic Renormalization of general dilaton-axion gravity
Papadimitriou, Ioannis
2011-01-01
We consider a very general dilaton-axion system coupled to Einstein-Hilbert gravity in arbitrary dimension and we carry out holographic renormalization for any dimension up to and including five dimensions. This is achieved by developing a new systematic algorithm for iteratively solving the radial Hamilton-Jacobi equation in a derivative expansion. The boundary term derived is valid not only for asymptotically AdS backgrounds, but also for more general asymptotics, including non-conformal branes and Improved Holographic QCD. In the second half of the paper, we apply the general result to Improved Holographic QCD with arbitrary dilaton potential. In particular, we derive the generalized Fefferman-Graham asymptotic expansions and provide a proof of the holographic Ward identities.
A Holographic Entanglement Entropy Conjecture for General Spacetimes
Sanches, Fabio
2016-01-01
We present a natural generalization of holographic entanglement entropy proposals beyond the scope of AdS/CFT by anchoring extremal surfaces to holographic screens. Holographic screens are a natural extension of the AdS boundary to arbitrary spacetimes and are preferred codimension 1 surfaces from the viewpoint of the covariant entropy bound. Screens have a unique preferred foliation into codimension 2 surfaces called leaves. Our proposal is to find the areas of extremal surfaces achored to the boundaries of regions in leaves. We show that the properties of holographic screens are sufficient to prove, under generic conditions, that extremal surfaces anchored in this way always lie within a causal region associated with a given leaf. Within this causal region, a maximin construction similar to that of Wall proves that our proposed quantity satisfies standard properties of entanglement entropy like strong subadditivity. We conjecture that our prescription computes entanglement entropies in quantum states that h...
Automated Digital Analysis Of Holographic Interferograms Of Pure Translations
Choudry, A.; Frankena, H. J.; van Beek, J. W.
1983-10-01
Holographic interferometry is a versatile technique for non-tactile measurement of changes in a wide variety of physical variables such as temperature, strain, position etc. It has a great potential for becoming an important metrologic technique in industrial applications. For holographic interferometry to become more attractive for industrial practice the problem of quantitative analysis of the patterns and thereby eliciting reliable values of the relevant parameters has to be addressed. In an attempt to calibrate the technique of holographic interferometry and ascertain the reliability of the subsequent digital analysis, we have chosen precisely known translations as a basis. Holographic interferograms taken from these are analysed manually and by digital techniques specially developed for such patterns. The results are promising enough to indicate the feasibility of automated digital analysis for determining translations within an acceptable accuracy. Some details of the evaluation techniques, along with a brief discussion of the preliminary results are presented.
Experiments on diffusion in liquids using holographic interferometry
Fenichel, Henry; Frankena, Hans; Groen, Fokke
1984-08-01
An experiment is described which uses the technique of holographic interferometry to study diffusion in liquids. The diffusion process can be recorded on double exposed holograms or it can be observed and recorded in real time using video techniques.
Entanglement Entropy for time dependent two dimensional holographic superconductor
Mazhari, N S; Myrzakulov, Kairat; Myrzakulov, R
2016-01-01
We studied entanglement entropy for a time dependent two dimensional holographic superconductor. We showed that the conserved charge of the system plays the role of the critical parameter to have condensation.
3D Holographic Technology and Its Educational Potential
Lee, Hyangsook
2013-01-01
This article discusses a number of significant developments in 3D holographic technology, its potential to revolutionize aspects of teaching and learning, and challenges of implementing the technology in educational settings.
Holographic entanglement and causal information in coherent states
Energy Technology Data Exchange (ETDEWEB)
Gentle, Simon A. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Rangamani, Mukund [Centre for Particle Theory & Department of Mathematical Sciences, Lower Mountjoy, South Road, Durham DH1 3LE (United Kingdom)
2014-01-22
Scalar solitons in global AdS{sub 4} are holographically dual to coherent states carrying a non-trivial condensate of a scalar operator. We study the holographic information content of these states, focusing on a particular spatial region, by examining the entanglement entropy and causal holographic information. We show generically that whenever the dimension of the condensed operator is sufficiently low (characterized by the double-trace operator becoming relevant), such coherent states have lower entanglement and causal holographic information than the vacuum state of the system, despite having greater energy. We also use these geometries to illustrate the fact that causal wedges associated with a simply-connected boundary region can have non-trivial topology even in causally trivial spacetimes.
Holographic storage scheme based on digital signal processing
Institute of Scientific and Technical Information of China (English)
Kebin Jia(贾克斌); Dapeng Yang(杨大鹏); Shubo Dun(敦书波); Shiquan Tao(陶世荃); Mingyan Qin(覃鸣燕)
2003-01-01
In this paper, a holographic storage scheme for multimedia data storage and retrieval based on the digitalsignal processing (DSP) is designed. A communication model for holographic storage system is obtainedon the analogy of traditional communication system. Many characteristics of holographic storage areembodied in the communication model. Then some new methods of DSP including two-dimensional (2-D)shifting interleaving, encoding and decoding of modulation-array (MA) code and method of soft-decision,etc. are proposed and employed in the system. From the results of experiments it can be seen that thosemeasures can effectively reduce the influence of noise. A segment of multimedia data, including video andaudio data, is retrieved successfully after holographic storage by using those techniques.
Holographic butterfly effect and diffusion in quantum critical region
Ling, Yi; Xian, Zhuo-Yu
2017-09-01
We investigate the butterfly effect and charge diffusion near the quantum phase transition in holographic approach. We argue that their criticality is controlled by the holographic scaling geometry with deformations induced by a relevant operator at finite temperature. Specifically, in the quantum critical region controlled by a single fixed point, the butterfly velocity decreases when deviating from the critical point. While, in the non-critical region, the behavior of the butterfly velocity depends on the specific phase at low temperature. Moreover, in the holographic Berezinskii-Kosterlitz-Thouless transition, the universal behavior of the butterfly velocity is absent. Finally, the tendency of our holographic results matches with the numerical results of Bose-Hubbard model. A comparison between our result and that in the O( N ) nonlinear sigma model is also given.
Review of Random Phase Encoding in Volume Holographic Storage
Directory of Open Access Journals (Sweden)
Wei-Chia Su
2012-09-01
Full Text Available Random phase encoding is a unique technique for volume hologram which can be applied to various applications such as holographic multiplexing storage, image encryption, and optical sensing. In this review article, we first review and discuss diffraction selectivity of random phase encoding in volume holograms, which is the most important parameter related to multiplexing capacity of volume holographic storage. We then review an image encryption system based on random phase encoding. The alignment of phase key for decryption of the encoded image stored in holographic memory is analyzed and discussed. In the latter part of the review, an all-optical sensing system implemented by random phase encoding and holographic interconnection is presented.
Holographic RG flows, entanglement entropy and the sum rule
Casini, Horacio; Torroba, Gonzalo
2015-01-01
We calculate the two-point function of the trace of the stress tensor in holographic renormalization group flows between pairs of conformal field theories. We show that the term proportional to the momentum squared in this correlator gives the change of the central charge between fixed points in d=2 and in d>2 it gives the holographic entanglement entropy for a planar region. This can also be seen as a holographic realization of the Adler-Zee formula for the renormalization of Newton's constant. Holographic regularization is found to provide a perfect match of the finite and divergent terms of the sum rule, and it is analogous to the regularization of the entropy in terms of mutual information. Finally, we provide a general proof of reflection positivity in terms of stability of the dual bulk action, and discuss the relation between unitarity constraints, the null energy condition and regularity in the interior of the gravity solution.
Can Holographic dark energy increase the mass of the wormhole?
Chattopadhyay, Surajit; Altaibayeva, Aziza; Myrzakulov, Ratbay
2014-01-01
In this work, we have studied accretion of dark energy (DE) onto Morris- Thorne wormhole with three different forms, namely, holographic dark energy, holographic Ricci dark energy and modified holographic Ricci dark energy . Considering the scale factor in power-law form we have observed that as the holographic dark energy accretes onto wormhole, the mass of the wormhole is decreasing. In the next phase we considered three parameterization schemes that are able to get hold of quintessence as well as phantom phases. Without any choice of scale factor we reconstructed Hubble parameter from conservation equation and dark energy densities and subsequently got the mass of the wormhole separately for accretion of the three dark energy candidates. It was observed that if these dark energies accrete onto the wormhole, then for quintessence stage, wormhole mass decreases up to a certain finite value and then again increases to aggressively during phantom phase of the universe.
Under The Dome: Doped holographic superconductors with broken translational symmetry
Baggioli, Matteo
2015-01-01
We comment on a simple way to accommodate translational symmetry breaking into the recently proposed holographic model which features a superconducting dome-shaped region on the temperature-doping phase diagram.
Avoiding Boltzmann Brain domination in holographic dark energy models
National Research Council Canada - National Science Library
Horvat, R
2015-01-01
.... The models of Dark Energy invoking holographic principle fit naturally into such a category, and spontaneous formation of isolated brains in otherwise empty space seems the most perplexing, creating...
Holographic entanglement entropy in 2D holographic superconductor via AdS3/CFT2
Directory of Open Access Journals (Sweden)
Davood Momeni
2015-07-01
Full Text Available The aim of the present letter is to find the holographic entanglement entropy (HEE in 2D holographic superconductors (HSC. Indeed, it is possible to compute the exact form of this entropy due to an advantage of approximate solutions inside normal and superconducting phases with backreactions. By making the UV and IR limits applied to the integrals, an approximate expression for HEE is obtained. In case the software cannot calculate minimal surface integrals analytically, it offers the possibility to proceed with a numerical evaluation of the corresponding terms. We'll understand how the area formula incorporates the structure of the domain wall approximation. We see that HEE changes linearly with belt angle. It's due to the extensivity of this type of entropy and the emergent of an entropic force. We find that the wider belt angle corresponds to a larger holographic surface. Another remarkable observation is that no “confinement/deconfinement” phase transition point exists in our 2D dual field theory. Furthermore, we observe that the slope of the HEE with respect to the temperature dSdT decreases, thanks to the emergence extra degree of freedom(s in low temperature system. A first order phase transition is detected near the critical point.
Holographic Refraction and the Measurement of Spherical Ametropia.
Nguyen, Nicholas Hoai Nam
2016-10-01
To evaluate the performance of a holographic logMAR chart for the subjective spherical refraction of the human eye. Bland-Altman analysis was used to assess the level of agreement between subjective spherical refraction using the holographic logMAR chart and conventional autorefraction and subjective spherical refraction. The 95% limits of agreement (LoA) were calculated between holographic refraction and the two standard methods (subjective and autorefraction). Holographic refraction has a lower mean spherical refraction when compared to conventional refraction (LoA 0.11 ± 0.65 D) and when compared to autorefraction (LoA 0.36 ± 0.77 D). After correcting for systemic bias, this is comparable between autorefraction and conventional subjective refraction (LoA 0.45 ± 0.79 D). After correcting for differences in vergence distance and chromatic aberration between holographic and conventional refraction, approximately 65% (group 1) of measurements between holography and conventional subjective refraction were similar (MD = 0.13 D, SD = 0.00 D). The remaining 35% (group 2) had a mean difference of 0.45 D (SD = 0.12 D) between the two subjective methods. Descriptive statistics showed group 2's mean age (21 years, SD = 13 years) was considerably lower than group 1's mean age (41 years, SD = 17), suggesting accommodation may have a role in the greater mean difference of group 2. Overall, holographic refraction has good agreement with conventional refraction and is a viable alternative for spherical subjective refraction. A larger bias between holographic and conventional refraction was found in younger subjects than older subjects, suggesting an association between accommodation and myopic over-correction during holographic refraction.
Holographic Gratings in Azobenzene Side-Chain Polymethacrylates
DEFF Research Database (Denmark)
Andruzzi, Luisa; Altomare, Angelina; Ciardelli, Francesco
1999-01-01
Optical storage properties of thin unoriented liquid crystalline and amorphous side-chain azobenzene polymethacrylate films are examined by polarization holographic measurements. The investigated materials are free radical copolymers derived from two photochromic monomers, 6-(4-oxy-4'-cyanoazoben......Optical storage properties of thin unoriented liquid crystalline and amorphous side-chain azobenzene polymethacrylate films are examined by polarization holographic measurements. The investigated materials are free radical copolymers derived from two photochromic monomers, 6-(4-oxy-4...