Dynamics of Bose-Einstein Condensates in Josephson Junctions

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ISBN 13 :
Total Pages : 212 pages
Book Rating : 4.:/5 (72 download)

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Book Synopsis Dynamics of Bose-Einstein Condensates in Josephson Junctions by : Jaclyn Semple

Download or read book Dynamics of Bose-Einstein Condensates in Josephson Junctions written by Jaclyn Semple and published by . This book was released on 2011 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: We numerically solve the Gross-Pitaevskii equation and the Bogoliubov de Gennes equations for a double well potential in order to model the dynamics of a Bose-Einstein condensate in a Josephson junction. First, the two dynamical regimes of the Josephson junction, that is, Josephson oscillations and self-trapping, are investigated under the application of a large sudden perturbation. It is found that the Josephson dynamics have a strong dependence on the strength of the interatomic interaction, and we observe the breakdown of the two-mode approximation. Second, we study the control of the dynamics through the use of a time-dependent, tilted double well potential. In the context of complete population transfer, the effect of the interactions on the adiabaticity and self-trapping is discussed in terms of a Landau-Zener-like model. We then explore the splitting of the condensate and the resulting dynamical behaviour by keeping the interaction strength constant, but changing the rate of the tilt sweep. Lastly, we examine the effect of the tilt sweep rate on the dynamics of population transfer. We observe a dependence of the self-trapping on the adiabaticity.

Many-Body Schrödinger Dynamics of Bose-Einstein Condensates

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Publisher : Springer Science & Business Media
ISBN 13 : 3642228666
Total Pages : 135 pages
Book Rating : 4.6/5 (422 download)

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Book Synopsis Many-Body Schrödinger Dynamics of Bose-Einstein Condensates by : Kaspar Sakmann

Download or read book Many-Body Schrödinger Dynamics of Bose-Einstein Condensates written by Kaspar Sakmann and published by Springer Science & Business Media. This book was released on 2011-08-31 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: At extremely low temperatures, clouds of bosonic atoms form what is known as a Bose-Einstein condensate. Recently, it has become clear that many different types of condensates -- so called fragmented condensates -- exist. In order to tell whether fragmentation occurs or not, it is necessary to solve the full many-body Schrödinger equation, a task that remained elusive for experimentally relevant conditions for many years. In this thesis the first numerically exact solutions of the time-dependent many-body Schrödinger equation for a bosonic Josephson junction are provided and compared to the approximate Gross-Pitaevskii and Bose-Hubbard theories. It is thereby shown that the dynamics of Bose-Einstein condensates is far more intricate than one would anticipate based on these approximations. A special conceptual innovation in this thesis are optimal lattice models. It is shown how all quantum lattice models of condensed matter physics that are based on Wannier functions, e.g. the Bose/Fermi Hubbard model, can be optimized variationally. This leads to exciting new physics.

Bose-Einstein Condensation

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Publisher : Oxford University Press
ISBN 13 : 9780198507192
Total Pages : 392 pages
Book Rating : 4.5/5 (71 download)

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Book Synopsis Bose-Einstein Condensation by : Lev. P. Pitaevskii

Download or read book Bose-Einstein Condensation written by Lev. P. Pitaevskii and published by Oxford University Press. This book was released on 2003-04-03 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bose-Einstein Condensation represents a new state of matter and is one of the cornerstones of quantum physics, resulting in the 2001 Nobel Prize. Providing a useful introduction to one of the most exciting field of physics today, this text will be of interest to a growing community of physicists, and is easily accessible to non-specialists alike.

Wave Turbulence

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Publisher : Springer Science & Business Media
ISBN 13 : 3642159419
Total Pages : 287 pages
Book Rating : 4.6/5 (421 download)

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Book Synopsis Wave Turbulence by : Sergey Nazarenko

Download or read book Wave Turbulence written by Sergey Nazarenko and published by Springer Science & Business Media. This book was released on 2011-02-12 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wave Turbulence refers to the statistical theory of weakly nonlinear dispersive waves. There is a wide and growing spectrum of physical applications, ranging from sea waves, to plasma waves, to superfluid turbulence, to nonlinear optics and Bose-Einstein condensates. Beyond the fundamentals the book thus also covers new developments such as the interaction of random waves with coherent structures (vortices, solitons, wave breaks), inverse cascades leading to condensation and the transitions between weak and strong turbulence, turbulence intermittency as well as finite system size effects, such as “frozen” turbulence, discrete wave resonances and avalanche-type energy cascades. This book is an outgrow of several lectures courses held by the author and, as a result, written and structured rather as a graduate text than a monograph, with many exercises and solutions offered along the way. The present compact description primarily addresses students and non-specialist researchers wishing to enter and work in this field.

Exotic Phases and Quantum Dynamics in Spin-Orbit Coupled Bose-Einstein Condensates

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (131 download)

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Book Synopsis Exotic Phases and Quantum Dynamics in Spin-Orbit Coupled Bose-Einstein Condensates by : Junpeng Hou

Download or read book Exotic Phases and Quantum Dynamics in Spin-Orbit Coupled Bose-Einstein Condensates written by Junpeng Hou and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, we study a range of exotic quantum phases and dynamics in BoseEinstein condensates (BECs) with spin-orbit (SO) coupling. Firstly, inspired by the recent experimental progresses in engineering supersolid stripe states in a SO-coupled BEC, we conjecture a new quantum state of matter called "superfluid-qausicrystal", in which quasicrystalline orders form spontaneously in the ground states of the BECs. We propose a realistic setup to prepare and observe this exotic quantum states and confirm its existence through both variational ansatz analysis and direct simulation of mean-field Gross-Pitaevskii equation (GPE). Moreover, we have identified rich phase diagram including superfluid-qausicrystals, supersoilds and plane-wave phases. By utilizing the double-well band structure of a SO-coupled BEC, we propose and investigate a momentum-pace Josephson junction (MSJJ). We show that, under an extra pair of Raman lasers, the two band minimums in momentum space can be weakly coupled. In such a MSJJ, Josephson currents can be induced not only by applying the equivalent of "voltages", but also by tuning tunneling phases. We characterize the MSJJs through both full mean-field analysis and a concise two-level model and demonstrate the important role of interactions between atoms. Besides, we experimentally demonstrate that this can be a route for realizing a striped BEC, providing an accessible platform to investigate the excitation spectra and other important properties of supersolid-like states. We observe coherent Rabi oscillations in momentum space between two band minima and demonstrate a long lifetime of the ground state, which find good agreements with mean-field simulations. Finally, we theoretically conceive and experimentally demonstrate a non-magnetic one-way spin switch device using a SO-coupled BEC subjected to a moving spin-independent repulsive dipole potential. We show that the physical foundation of this unidirectional device is based on the breakdown of Galilean invariance in the presence of SO coupling. The experimental observation, the numerical simulations and the theoretic interpretations are consistent with the others

Non-equilibrium Dynamics of Tunnel-Coupled Superfluids

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Publisher : Springer Nature
ISBN 13 : 3030528448
Total Pages : 204 pages
Book Rating : 4.0/5 (35 download)

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Book Synopsis Non-equilibrium Dynamics of Tunnel-Coupled Superfluids by : Marine Pigneur

Download or read book Non-equilibrium Dynamics of Tunnel-Coupled Superfluids written by Marine Pigneur and published by Springer Nature. This book was released on 2020-08-28 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: The relaxation of isolated quantum many-body systems is a major unsolved problem of modern physics, which is connected to many fundamental questions. However, realizations of quantum many-body systems which are both well isolated from their environment and accessible to experimental study are scarce. In recent years, the field has experienced rapid progress, partly attributed to ultra-cold atoms. This book presents the experimental study of a relaxation phenomenon occurring in a one-dimensional bosonic Josephson junction. The system consists of two 1D quasi Bose-Einstein condensates of 87Rb, magnetically trapped on an atom chip. Using radio-frequency dressing, the author deforms a single harmonic trap, in which the atoms are initially condensed, into a double-well potential and realizes a splitting of the wave function. A large spatial separation and a tilt of the double-well enable the preparation of a broad variety of initial states by precisely adjusting the initial population and relative phase of the two wave packets, while preserving the phase coherence. By re-coupling the two wave packets, the author investigates tunneling regimes such as Josephson (plasma) oscillations and macroscopic quantum self-trapping. In both regimes, the tunneling dynamics exhibits a relaxation to a phase-locked equilibrium state contradicting theoretical predictions. The experimental results are supported with an empirical model that allows quantitative discussions according to various experimental parameters. These results illustrate how strongly the non-equilibrium dynamics differ from the equilibrium one, which is well described by thermodynamics and statistical physics.

Bose-Einstein Condensation

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Publisher : DIANE Publishing
ISBN 13 : 0788137409
Total Pages : 213 pages
Book Rating : 4.7/5 (881 download)

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Book Synopsis Bose-Einstein Condensation by : Keith Burnett (Ed); Mark Edwar

Download or read book Bose-Einstein Condensation written by Keith Burnett (Ed); Mark Edwar and published by DIANE Publishing. This book was released on 1996-12 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Among the most remarkable effects that quantum mechanics adds to the catalog of the thermal properties of matter is "condensation" of an ideal gas of identical particles into a single quantum state, the principle of which was discovered in the theory of statistical mechanics by Bose and Einstein in the 1920s. Bose-Einstein condensation (BEC) is a mechanism for producing a macroscopic quantum system, and is exemplary of the macroscopic quantum phenomena of superconductivity and superfluidity.These 15 papers provide an introduction to current work on BEC.

Interferometry with Interacting Bose-Einstein Condensates in a Double-Well Potential

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Publisher : Springer
ISBN 13 : 3319272330
Total Pages : 244 pages
Book Rating : 4.3/5 (192 download)

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Book Synopsis Interferometry with Interacting Bose-Einstein Condensates in a Double-Well Potential by : Tarik Berrada

Download or read book Interferometry with Interacting Bose-Einstein Condensates in a Double-Well Potential written by Tarik Berrada and published by Springer. This book was released on 2015-12-17 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis demonstrates a full Mach–Zehnder interferometer with interacting Bose–Einstein condensates confined on an atom chip. It relies on the coherent manipulation of atoms trapped in a magnetic double-well potential, for which the author developed a novel type of beam splitter. Particle-wave duality enables the construction of interferometers for matter waves, which complement optical interferometers in precision measurement devices, both for technological applications and fundamental tests. This requires the development of atom-optics analogues to beam splitters, phase shifters and recombiners. Particle interactions in the Bose–Einstein condensate lead to a nonlinearity, absent in photon optics. This is exploited to generate a non-classical state with reduced atom-number fluctuations inside the interferometer. This state is then used to study the interaction-induced dephasing of the quantum superposition. The resulting coherence times are found to be a factor of three longer than expected for coherent states, highlighting the potential of entanglement as a resource for quantum-enhanced metrology.

Spin Squeezing and Non-linear Atom Interferometry with Bose-Einstein Condensates

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Publisher : Springer Science & Business Media
ISBN 13 : 3642256368
Total Pages : 123 pages
Book Rating : 4.6/5 (422 download)

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Book Synopsis Spin Squeezing and Non-linear Atom Interferometry with Bose-Einstein Condensates by : Christian Groß

Download or read book Spin Squeezing and Non-linear Atom Interferometry with Bose-Einstein Condensates written by Christian Groß and published by Springer Science & Business Media. This book was released on 2012-01-13 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interferometry, the most precise measurement technique known today, exploits the wave-like nature of the atoms or photons in the interferometer. As expected from the laws of quantum mechanics, the granular, particle-like features of the individually independent atoms or photons are responsible for the precision limit, the shot noise limit. However this “classical” bound is not fundamental and it is the aim of quantum metrology to overcome it by employing entanglement among the particles. This work reports on the realization of spin-squeezed states suitable for atom interferometry. Spin squeezing was generated on the basis of motional and spin degrees of freedom, whereby the latter allowed the implementation of a full interferometer with quantum-enhanced precision.

Measurement of the A.C. Josephson Effect in a Bose-Einstein Condensate

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Publisher :
ISBN 13 :
Total Pages : 75 pages
Book Rating : 4.:/5 (87 download)

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Book Synopsis Measurement of the A.C. Josephson Effect in a Bose-Einstein Condensate by : Shahar Levy

Download or read book Measurement of the A.C. Josephson Effect in a Bose-Einstein Condensate written by Shahar Levy and published by . This book was released on 2008 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Quantum Gases

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Publisher : World Scientific
ISBN 13 : 1848168128
Total Pages : 579 pages
Book Rating : 4.8/5 (481 download)

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Book Synopsis Quantum Gases by : Nick Proukakis

Download or read book Quantum Gases written by Nick Proukakis and published by World Scientific. This book was released on 2013 with total page 579 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides a broad overview of the principal theoretical techniques applied to non-equilibrium and finite temperature quantum gases. Covering Bose-Einstein condensates, degenerate Fermi gases, and the more recently realised exciton-polariton condensates, it fills a gap by linking between different methods with origins in condensed matter physics, quantum field theory, quantum optics, atomic physics, and statistical mechanics.

Spin Squeezing and Non-linear Atom Interferometry with Bose-Einstein Condensates

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Publisher : Springer Science & Business Media
ISBN 13 : 3642256376
Total Pages : 123 pages
Book Rating : 4.6/5 (422 download)

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Book Synopsis Spin Squeezing and Non-linear Atom Interferometry with Bose-Einstein Condensates by : Christian Groß

Download or read book Spin Squeezing and Non-linear Atom Interferometry with Bose-Einstein Condensates written by Christian Groß and published by Springer Science & Business Media. This book was released on 2012-01-12 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interferometry, the most precise measurement technique known today, exploits the wave-like nature of the atoms or photons in the interferometer. As expected from the laws of quantum mechanics, the granular, particle-like features of the individually independent atoms or photons are responsible for the precision limit, the shot noise limit. However this “classical” bound is not fundamental and it is the aim of quantum metrology to overcome it by employing entanglement among the particles. This work reports on the realization of spin-squeezed states suitable for atom interferometry. Spin squeezing was generated on the basis of motional and spin degrees of freedom, whereby the latter allowed the implementation of a full interferometer with quantum-enhanced precision.

Bose-einstein Condensation - From Atomic Physics To Quantum Fluids, Procs Of The 13th Physics Summer Sch

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Publisher : World Scientific
ISBN 13 : 9814491985
Total Pages : 315 pages
Book Rating : 4.8/5 (144 download)

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Book Synopsis Bose-einstein Condensation - From Atomic Physics To Quantum Fluids, Procs Of The 13th Physics Summer Sch by : Mukunda Prasad Das

Download or read book Bose-einstein Condensation - From Atomic Physics To Quantum Fluids, Procs Of The 13th Physics Summer Sch written by Mukunda Prasad Das and published by World Scientific. This book was released on 2000-12-28 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bose-Einstein condensation of dilute gases is an exciting new field of interdisciplinary physics. The eight chapters in this volume introduce its theoretical and experimental foundations. The authors are lucid expositors who have also made outstanding contributions to the field. They include theorists Tony Leggett, Allan Griffin and Keith Burnett, and Nobel-Prize-winning experimentalist Bill Phillips. In addition to the introductory material, there are articles treating topics at the forefront of research, such as experimental quantum phase engineering of condensates, the “superchemistry” of interacting atomic and molecular condensates, and atom laser theory.

The Physics of Exciton-Polariton Condensates

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Publisher : CRC Press
ISBN 13 : 1482212153
Total Pages : 178 pages
Book Rating : 4.4/5 (822 download)

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Book Synopsis The Physics of Exciton-Polariton Condensates by : Konstantinos Lagoudakis

Download or read book The Physics of Exciton-Polariton Condensates written by Konstantinos Lagoudakis and published by CRC Press. This book was released on 2013-12-02 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: After the first demonstration of Bose Einstein condensation in the solid state in 2006 and the establishment of exciton polariton condensates in the wider scientific community, an intense interest has been attracted by this phenomenon at both theoretical and experimental level. This book presents in detail the different aspects of fundamental impor

Physics and Applications of the Josephson Effect

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Publisher : Wiley-VCH
ISBN 13 :
Total Pages : 568 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Physics and Applications of the Josephson Effect by : Antonio Barone

Download or read book Physics and Applications of the Josephson Effect written by Antonio Barone and published by Wiley-VCH. This book was released on 1982-05-14 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cover -- Contents -- CHAPTER 1 Weak Superconductivity8212; Phenomenological Aspects -- 146;1 Macroscopic Quantum System -- 146;2 Coupled Superconductors -- 146;3 Single Electron Tunneling -- 146;4 Josephson Equations -- 146;5 Magnetic Field Effects -- 146;6 Barrier Free Energy -- 146;7 Electrodynamics of the Josephson Junction -- 146;8 Other Josephson Structures -- CHAPTER 2 Microscopic Theory -- 1 Tunneling Hamiltonian Formalism -- 2 General Expression for the Total Current -- 3 Tunneling Current for Constant Voltage -- 4 Expressions of Iqpi44; Iqp44; IJ144; IJ2 -- 5 Tunneling Current in the B46;C46;S46; Approximation -- 6 The 34;cos w34; Problem -- CHAPTER 3 Magnitude and Temperature Dependence of the Critical Current -- 346;1 Josephson Current for V61;0 -- 346;2 B46;C46;S46; Approximation -- 346;3 Strong Coupling Effects -- 346;4 Effects of Paramagnetic Impurities -- 346;5 Measurement Techniques -- CHAPTER 4 34;Small34; Junctions in a Magnetic Field -- 446;1 Josephson Penetration Depth -- 446;2 Small Junctions -- 446;3 Uniform Tunneling Current Distribution -- 446;4 Nonuniform Tunneling Current Density -- CHAPTER 5 Large Junctions8212;Static Self45;Field Effects -- 546;1 Approximate Analysis -- 546;2 Analysis of Owen and Scalapino -- 546;3 Effects of the Junction Geometrical Configuration -- CHAPTER 6 Voltage Current Characteristics -- 646;1 V45;I Curves of Various Weak Links -- 646;2 Resistively Shunted Junction Model58; Autonomous Case -- 646;3 Current Biased Tunneling Junction -- 646;4 Effects of Thermal Fluctuations -- CHAPTER 7 Other Superconducting Weak Link Structures -- 746;1 Metal Barrier Junctions -- 746;2 Semiconducting Barrier Junctions -- 746;3 Bridge45;Type Junctions -- 746;4 Point Contact Weak Links -- CHAPTER 8 Device Fabrication Technology -- 846;1 Josephson Tunneling Junctions -- 846;2 Junction Electrodes -- 846;3 Oxide Barriers -- 846;4 Junction Patterning -- 846;5 Simple Procedures for Preparing Oxide Barrier Junctions -- 846;6 Semiconductor Barriers -- 846;7 Bridge45;Type Weak Links -- 846;8 Point Contact Structures -- CHAPTER 9 Resonant Modes In Tunneling Structures -- 946;1 Josephson Junction as a Transmission Line -- 946;2 Resonant Modes for Low Q Junctions -- 946;3 Junction of Infinite Length -- 946;4 Nonuniform Current Density Distribution -- CHAPTER 10 Fluxon Dynamics -- 1046;1 The Sine Gordon Equation -- 1046;2 Nonlinear Standing Waves on a Rectangular Junction -- 1046;3 Effects of Losses and Bias -- 1046;4 Zero Field Steps -- 1046;5 Perturbative Analysis of Fluxon Dynamics -- 1046;6 Effects of Flux Flow on D46;C46; Voltage45;Current Characteristics -- 1046;7 Two Dimensional Junctions -- CHAPTER 11 High Frequency Properties and Applications of the Josephson Effect -- 1146;1 Simple Voltage Source Model -- 1146;2 Tunneling Junctions in External Microwave Radiation -- 1146;3 Current Source Model -- 1146;4 Emission of Radiation -- 1146;5 Detection of Radiation -- 1146;6 Parametric Amplification -- 1146;7 The Determina.

Observation of the D.c. Josephson Effect in a Bose-Einstein Condensate of Dilute Atomic Vapor

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Publisher :
ISBN 13 :
Total Pages : 55 pages
Book Rating : 4.:/5 (87 download)

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Book Synopsis Observation of the D.c. Josephson Effect in a Bose-Einstein Condensate of Dilute Atomic Vapor by : Itay Shomroni

Download or read book Observation of the D.c. Josephson Effect in a Bose-Einstein Condensate of Dilute Atomic Vapor written by Itay Shomroni and published by . This book was released on 2008 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Spontaneous Symmetry Breaking, Self-Trapping, and Josephson Oscillations

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Publisher : Springer Science & Business Media
ISBN 13 : 3642212077
Total Pages : 712 pages
Book Rating : 4.6/5 (422 download)

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Book Synopsis Spontaneous Symmetry Breaking, Self-Trapping, and Josephson Oscillations by : Boris A. Malomed

Download or read book Spontaneous Symmetry Breaking, Self-Trapping, and Josephson Oscillations written by Boris A. Malomed and published by Springer Science & Business Media. This book was released on 2014-07-08 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume collects a a number of contributions on spontaneous symmetry breaking. Current studies in this general field are going ahead at a full speed. The book present review chapters which give an overview on the major break throughs of recent years. It covers a number of different physical settings which are introduced when a nonlinearity is added to the underlying symmetric problems and its strength exceeds a certain critical value. The corresponding loss of symmetry, called spontaneous symmetry breaking, alias self-trapping into asymmetric states is extensively discussed in this book. The book presents both active theoretical studies of spontaneous symmetry breaking effects as well as experimental findings, chiefly for Bose-Einstein-Condensates with the self-repulsive nonlinearity, and also for photorefractive media in optics.