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Abbas K, Boudjemâa A. Binary Bose-Einstein condensates in a disordered time-dependent potential. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:125102. [PMID: 34929676 DOI: 10.1088/1361-648x/ac44d3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
We study the non-equilibrium evolution of binary Bose-Einstein condensates in the presence of a weak random potential with Gaussian correlation function using the time-dependent perturbation theory. We apply this theory to construct a closed set of equations that highlight the role of the spectacular interplay between the disorder and the interspecies interactions in the time evolution of the density induced by disorder in each component. It is found that this latter increases with time favoring localization of both species. The time scale at which the theory remains valid depends on the respective system parameters. We show analytically and numerically that such a system supports a steady state that periodically changing during its time propagation. The obtained dynamical corrections indicate that disorder may transform the system into a stationary out-of-equilibrium states. Understanding this time evolution is pivotal for the realization of Floquet condensates.
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Affiliation(s)
- Karima Abbas
- Department of Physics, Faculty of Exact Sciences and Informatics, Hassiba Benbouali University of Chlef, PO Box 78, 02000, Ouled-Fares, Chlef, Algeria
- Laboratory of Mechanics and Energy, Hassiba Benbouali University of Chlef, PO Box 78, 02000, Ouled-Fares, Chlef, Algeria
| | - Abdelâali Boudjemâa
- Department of Physics, Faculty of Exact Sciences and Informatics, Hassiba Benbouali University of Chlef, PO Box 78, 02000, Ouled-Fares, Chlef, Algeria
- Laboratory of Mechanics and Energy, Hassiba Benbouali University of Chlef, PO Box 78, 02000, Ouled-Fares, Chlef, Algeria
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2
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Liu D, Xiong C, Liu X. Vectorizing Quantum Turbulence Vortex-Core Lines for Real-Time Visualization. IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 2021; 27:3794-3807. [PMID: 32191891 DOI: 10.1109/tvcg.2020.2981460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Vectorizing vortex-core lines is crucial for high-quality visualization and analysis of turbulence. While several techniques exist in the literature, they can only be applied to classical fluids. As quantum fluids with turbulence are gaining attention in physics, extracting and visualizing vortex-core lines for quantum fluids is increasingly desirable. In this article, we develop an efficient vortex-core line vectorization method for quantum fluids enabling real-time visualization of high-resolution quantum turbulence structure. From a dataset obtained through simulation, our technique first identifies vortex nodes based on the circulation field. To vectorize the vortex-core lines interpolating these vortex nodes, we propose a novel graph-based data structure, with iterative graph reduction and density-guided local optimization, to locate sub-grid-scale vortex-core line samples more precisely, which are then vectorized by continuous curves. This vortex-core representation naturally captures complex topology, such as branching during reconnection. Our vectorization approach reduces memory consumption by orders of magnitude, enabling real-time visualization performance. Different types of interactive visualizations are demonstrated to show the effectiveness of our technique, which could help further research on quantum turbulence.
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Localisation of weakly interacting bosons in two dimensions: disorder vs lattice geometry effects. Sci Rep 2019; 9:11049. [PMID: 31363111 PMCID: PMC6667487 DOI: 10.1038/s41598-019-47279-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 07/02/2019] [Indexed: 11/24/2022] Open
Abstract
We investigate the effects of disorder and lattice geometry against localisation phenomena in a weakly interacting ultracold bosonic gas confined in a 2D optical lattice. The behaviour of the quantum fluid is studied at the mean-field level performing computational experiments, as a function of disorder strength for lattices of sizes similar to current experiments. Quantification of localisation, away from the Bose glass phase, was obtained directly from the stationary density profiles through a robust statistical analysis of the condensate component, as a function of the disorder amplitude. Our results show a smooth transition, or crossover, to localisation induced by disorder in square and triangular lattices. In contrast, associated to its larger tunneling amplitude, honeycomb lattices show absence of localisation for the same range of disorder strengths and same lattice amplitude, while also exhibiting partial localisation for large disorder amplitudes. We also conclude that the coordination number z have a partial influence on how fast this smooth transition occurs as the system size increases. Signatures of disorder are also found in the ground state energy spectrum, where a continuous distribution emerges instead of a distribution of sharp peaks proper to the system in the absence of disorder.
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Abstract
We present a field-theory description of ultracold bosonic atoms in the presence of a disordered external potential. By means of functional integration techniques, we aim to investigate and review the interplay between disordered energy landscapes and fluctuations, both thermal and quantum ones. Within the broken-symmetry phase, up to the Gaussian level of approximation, the disorder contribution crucially modifies both the condensate depletion and the superfluid response. Remarkably, it is found that the ordered (i.e., superfluid) phase can be destroyed also in regimes where the random external potential is suitable for a perturbative analysis. We analyze the simplest case of quenched disorder and then we move to present the implementation of the replica trick for ultracold bosonic systems. In both cases, we discuss strengths and limitations of the reviewed approach, paying specific attention to possible extensions and the most recent experimental outputs.
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Bertoli G, Michal VP, Altshuler BL, Shlyapnikov GV. Finite-Temperature Disordered Bosons in Two Dimensions. PHYSICAL REVIEW LETTERS 2018; 121:030403. [PMID: 30085818 DOI: 10.1103/physrevlett.121.030403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Indexed: 06/08/2023]
Abstract
We study phase transitions in a two dimensional weakly interacting Bose gas in a random potential at finite temperatures. We identify superfluid, normal fluid, and insulator phases and construct the phase diagram. At T=0 one has a tricritical point where the three phases coexist. The truncation of the energy distribution at the trap barrier, which is a generic phenomenon in cold atom systems, limits the growth of the localization length and in contrast to the thermodynamic limit the insulator phase is present at any temperature.
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Affiliation(s)
- G Bertoli
- LPTMS, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Orsay 91405, France
| | - V P Michal
- QuTech and Kavli Institute of Nanoscience, TU Delft, 2600 GA Delft, Netherlands
| | - B L Altshuler
- Physics Department, Columbia University, 538 West 120th Street, New York, New York 10027, USA
| | - G V Shlyapnikov
- LPTMS, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Orsay 91405, France
- SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay, Gif sur Yvette 91191, France
- Russian Quantum Center, Skolkovo, Moscow Region 143025, Russia
- Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
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6
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Janot A, Hyart T, Eastham PR, Rosenow B. Superfluid stiffness of a driven dissipative condensate with disorder. PHYSICAL REVIEW LETTERS 2013; 111:230403. [PMID: 24476236 DOI: 10.1103/physrevlett.111.230403] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 10/25/2013] [Indexed: 06/03/2023]
Abstract
Observations of macroscopic quantum coherence in driven systems, e.g. polariton condensates, have strongly stimulated experimental as well as theoretical efforts during the last decade. We address the question of whether a driven quantum condensate is a superfluid, allowing for the effects of disorder and its nonequilibrium nature. We predict that for spatial dimensions d<4 the superfluid stiffness vanishes once the condensate exceeds a critical size, and treat in detail the case d=2. Thus a nonequilibrium condensate is not a superfluid in the thermodynamic limit, even for weak disorder, although superfluid behavior would persist in small systems.
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Affiliation(s)
- Alexander Janot
- Institut für Theoretische Physik, Universität Leipzig, 04009 Leipzig, Germany
| | - Timo Hyart
- Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, Netherlands
| | - Paul R Eastham
- School of Physics and CRANN, Trinity College, Dublin 2, Ireland
| | - Bernd Rosenow
- Institut für Theoretische Physik, Universität Leipzig, 04009 Leipzig, Germany
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7
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Geiger T, Wellens T, Buchleitner A. Inelastic multiple scattering of interacting bosons in weak random potentials. PHYSICAL REVIEW LETTERS 2012; 109:030601. [PMID: 22861833 DOI: 10.1103/physrevlett.109.030601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Indexed: 06/01/2023]
Abstract
We develop a diagrammatic scattering theory for interacting bosons in a three-dimensional, weakly disordered potential. We show how collisional energy transfer between the bosons induces the thermalization of the inelastic single-particle current which, after only a few collision events, dominates over the elastic contribution described by the Gross-Pitaevskii ansatz.
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Affiliation(s)
- Tobias Geiger
- Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, D-79104 Freiburg, Germany
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8
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Zhou K, Zhang Z. Opposite effect of spin-orbit coupling on condensation and superfluidity. PHYSICAL REVIEW LETTERS 2012; 108:025301. [PMID: 22324694 DOI: 10.1103/physrevlett.108.025301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Indexed: 05/31/2023]
Abstract
We investigate the effects of Rashba-type spin-orbit coupling (SOC) on the condensed density and superfluid density tensor of a two-component Fermi gas in the BCS-BEC crossover at zero temperature. In anisotropic three dimensions (3D), we find that SOC has an opposite effect on condensation (enhanced) and superfluidity (suppressed in the SOC direction), and this effect becomes most pronounced for very weak interactions and the SOC strength being larger than a characteristic value. Furthermore, as functions of SOC strength, the condensed density changes monotonically for all interaction parameters, while the superfluid density has a minimum when the interaction parameter is below a critical value. We also discuss the isotropic two-dimensional case where analytical expressions for the gap and number equations are obtained and the same phenomena are found as that of the 3D case.
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Affiliation(s)
- Kezhao Zhou
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, People's Republic of China
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Pilati S, Giorgini S, Prokof'ev N. Superfluid transition in a bose gas with correlated disorder. PHYSICAL REVIEW LETTERS 2009; 102:150402. [PMID: 19518606 DOI: 10.1103/physrevlett.102.150402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 03/05/2009] [Indexed: 05/27/2023]
Abstract
The superfluid transition of a three-dimensional gas of hard-sphere bosons in a disordered medium is studied using quantum Monte Carlo methods. Simulations are performed in continuous space both in the canonical and in the grand-canonical ensemble. At fixed density we calculate the shift of the transition temperature as a function of the disorder strength, while at fixed temperature we determine both the critical chemical potential and the critical density separating normal and superfluid phases. In the regime of strong disorder the normal phase extends up to large values of the degeneracy parameter, and the critical chemical potential exhibits a linear dependence in the intensity of the random potential. The role of interactions and disorder correlations is also discussed.
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Affiliation(s)
- S Pilati
- Dipartimento di Fisica, Università di Trento and CNR-INFM BEC Center, I-38050 Povo, Trento, Italy
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10
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Bossy J, Pearce JV, Schober H, Glyde HR. Phonon-roton modes and localized Bose-Einstein condensation in liquid helium under pressure in nanoporous media. PHYSICAL REVIEW LETTERS 2008; 101:025301. [PMID: 18764191 DOI: 10.1103/physrevlett.101.025301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Revised: 06/10/2008] [Indexed: 05/26/2023]
Abstract
We show, using inelastic neutron scattering, that liquid helium in porous media, two gelsils and MCM-41, supports a phonon-roton mode up to a pressure of 36-37 bars only. Modes having the highest energy ("maxons") broaden and become unobservable at the lowest pressures (p approximately 26 bars) while rotons survive to the highest pressure. By comparing with the superfluid density observed by Yamamoto and co-workers in gelsil, we propose that there is a Bose glass phase containing islands of BEC surrounding the superfluid phase.
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Affiliation(s)
- Jacques Bossy
- Institut Néel, CNRS-UJF, BP 166, 38042 Grenoble Cedex 9, France
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11
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Nattermann T, Pokrovsky VL. Bose-Einstein condensates in strongly disordered traps. PHYSICAL REVIEW LETTERS 2008; 100:060402. [PMID: 18352445 DOI: 10.1103/physrevlett.100.060402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 10/25/2007] [Indexed: 05/26/2023]
Abstract
A Bose-Einstein condensate in an external potential consisting of a superposition of a harmonic and a random potential is considered theoretically. From a semiquantitative analysis we find the size, shape, and excitation energy as a function of the disorder strength. For positive scattering length and sufficiently strong disorder the condensate decays into fragments each of the size of the Larkin length L. This state is stable over a large range of particle numbers. The frequency of the breathing mode scales as 1/L(2). For negative scattering length a condensate of size L may exist as a metastable state. These findings are generalized to anisotropic traps.
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Affiliation(s)
- T Nattermann
- Institut für Theoretische Physik, Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln, Germany.
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12
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Orso G. BCS-BEC crossover in a random external potential. PHYSICAL REVIEW LETTERS 2007; 99:250402. [PMID: 18233500 DOI: 10.1103/physrevlett.99.250402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2007] [Revised: 10/24/2007] [Indexed: 05/25/2023]
Abstract
We investigate the ground state properties of a disordered superfluid Fermi gas across the BCS-BEC (Bose-Einstein condensate) crossover. We show that, for weak disorder, both the depletion of the condensate fraction of pairs and the normal fluid density exhibit a nonmonotonic behavior as a function of the interaction parameter 1/k{F}a, reaching their minimum value near unitarity. We find that, moving away from the weak-coupling BCS regime, Anderson's theorem ceases to apply and the superfluid order parameter is more and more affected by the random potential.
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Affiliation(s)
- G Orso
- Laboratoire Physique Théorique et Modèles Statistiques, Université Paris Sud, Bat. 100, 91405 Orsay Cedex, France
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13
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Lugan P, Clément D, Bouyer P, Aspect A, Sanchez-Palencia L. Anderson localization of Bogolyubov quasiparticles in interacting Bose-Einstein condensates. PHYSICAL REVIEW LETTERS 2007; 99:180402. [PMID: 17995384 DOI: 10.1103/physrevlett.99.180402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Indexed: 05/25/2023]
Abstract
We study the Anderson localization of Bogolyubov quasiparticles in an interacting Bose-Einstein condensate (with a healing [corrected] length xi) subjected to a random potential (with a finite correlation length sigma(R)). We derive analytically the Lyapunov exponent as a function of the quasiparticle momentum k, and we study the localization maximum k(max). For 1D speckle potentials, we find that k(max) proportional variant 1/xi when xi>>sigma(R) while k(max) proportional variant 1/sigma(R) when xi<<sigma(R), and that the localization is strongest when xi approximately sigma(R). Numerical calculations support our analysis, and our estimates indicate that the localization of the Bogolyubov quasiparticles is accessible in experiments with ultracold atoms.
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Affiliation(s)
- P Lugan
- Laboratoire Charles Fabry de l'Institut d'Optique, CNRS and Univ. Paris-Sud, Campus Polytechnique, RD 128, F-91127 Palaiseau cedex, France
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14
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Paul T, Schlagheck P, Leboeuf P, Pavloff N. Superfluidity versus Anderson localization in a dilute Bose gas. PHYSICAL REVIEW LETTERS 2007; 98:210602. [PMID: 17677757 DOI: 10.1103/physrevlett.98.210602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Indexed: 05/16/2023]
Abstract
We consider the motion of a quasi-one-dimensional beam of Bose-Einstein condensed particles in a disordered region of finite extent. Interaction effects lead to the appearance of two distinct regions of stationary flow. One is subsonic and corresponds to superfluid motion. The other one is supersonic and dissipative and shows Anderson localization. We compute analytically the interaction-dependent localization length. We also explain the disappearance of the supersonic stationary flow for large disordered samples.
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Affiliation(s)
- T Paul
- Laboratoire de Physique Théorique et Modèles Statistiques, CNRS, Université Paris Sud, UMR8626, 91405 Orsay Cedex, France
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15
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Clément D, Varón AF, Hugbart M, Retter JA, Bouyer P, Sanchez-Palencia L, Gangardt DM, Shlyapnikov GV, Aspect A. Suppression of transport of an interacting elongated Bose-Einstein condensate in a random potential. PHYSICAL REVIEW LETTERS 2005; 95:170409. [PMID: 16383806 DOI: 10.1103/physrevlett.95.170409] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Indexed: 05/05/2023]
Abstract
We observe the suppression of the 1D transport of an interacting elongated Bose-Einstein condensate in a random potential with an amplitude that is small compared to the typical energy per atom, dominated by the interaction energy. Numerical calculations reproduce our observations well. We propose a scenario for disorder-induced trapping of the condensate in agreement with our findings.
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Affiliation(s)
- D Clément
- Laboratoire Charles Fabry, Institut d'Optique, Université Paris-Sud XI, 91403 Orsay Cedex, France
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16
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Bilas N, Pavloff N. Propagation of a dark soliton in a disordered Bose-Einstein condensate. PHYSICAL REVIEW LETTERS 2005; 95:130403. [PMID: 16197124 DOI: 10.1103/physrevlett.95.130403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2005] [Indexed: 05/04/2023]
Abstract
We consider the propagation of a dark soliton in a quasi-1D Bose-Einstein condensate in presence of a random potential. This configuration involves nonlinear effects and disorder, and we argue that, contrarily to the study of stationary transmission coefficients through a nonlinear disordered slab, it is a well-defined problem. It is found that a dark soliton decays algebraically, over a characteristic length which is independent of its initial velocity, and much larger than both the healing length and the 1D scattering length of the system. We also determine the characteristic decay time.
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Affiliation(s)
- Nicolas Bilas
- Laboratoire de Physique Théorique et Modèles Statistiques, Université Paris Sud, bât. 100, F-91405 Orsay Cedex, France
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17
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Lye JE, Fallani L, Modugno M, Wiersma DS, Fort C, Inguscio M. Bose-Einstein condensate in a random potential. PHYSICAL REVIEW LETTERS 2005; 95:070401. [PMID: 16196765 DOI: 10.1103/physrevlett.95.070401] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Indexed: 05/04/2023]
Abstract
An optical speckle potential is used to investigate the static and dynamic properties of a Bose-Einstein condensate in the presence of disorder. With small levels of disorder, stripes are observed in the expanded density profile and strong damping of dipole and quadrupole oscillations is seen. Uncorrelated frequency shifts of the two modes are measured and are explained using a sum-rules approach and by the numerical solution of the Gross-Pitaevskii equation.
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Affiliation(s)
- J E Lye
- LENS, Dipartimento di Fisica, and INFM Università di Firenze, Sesto Fiorentino (FI), Italy.
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18
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Schwartz M. Bose-Einstein condensation and the glassy state. PHYSICAL REVIEW LETTERS 2004; 93:205701. [PMID: 15600940 DOI: 10.1103/physrevlett.93.205701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2004] [Indexed: 05/24/2023]
Abstract
The distinction between a classical glass and a classical liquid is difficult, since both are disordered. The difference is in the fact that a glass is frozen while the liquid is not. In this Letter an equilibrium measure is suggested that distinguishes between a glass and a liquid. The choice of this measure is based on the idea that in a system which is not frozen symmetry under permutation of particles is physically relevant, because particles can be permuted by actual physical motion. This is not the case in a frozen system. In this Letter it is shown how to generalize naturally the quantum mechanical concept of Bose condensed fraction to classical systems in order to distinguish between the glass and the liquid. It is finite in the liquid and zero in the frozen state. The actual value of the condensed fraction in the liquid may serve also as a measure of the glassiness in the liquid.
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Affiliation(s)
- Moshe Schwartz
- School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
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19
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Mayers J. Bose-Einstein condensation, phase coherence, and two-fluid behavior in 4He. PHYSICAL REVIEW LETTERS 2004; 92:135302. [PMID: 15089620 DOI: 10.1103/physrevlett.92.135302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2003] [Indexed: 05/24/2023]
Abstract
It is shown that the assumption that the many particle wave functions describing superfluid 4He have some phase coherence properties of correlated basis functions provides a new explanation of the link between Bose-Einstein condensation and two fluid behavior. This assumption also implies that the condensate fraction is proportional to the superfluid fraction, in agreement with experiment, and provides a simple quantitative explanation of the anomalous reduction in spatial order and liquid density, observed as the temperature is lowered in superfluid 4He.
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Affiliation(s)
- J Mayers
- Rutherford Appleton Laboratory, Chilton OX11 0QX, United Kingdom
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20
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Lopatin AV, Vinokur VM. Delocalization in two-dimensional disordered Bose systems and depinning transition in the vortex state in superconductors. PHYSICAL REVIEW LETTERS 2004; 92:067008. [PMID: 14995269 DOI: 10.1103/physrevlett.92.067008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2003] [Indexed: 05/24/2023]
Abstract
We investigate a two-dimensional (2D) Bose system with the long range interactions in the presence of disorder. Formation of the bound states at strong impurity sites gives rise to a depletion of the superfluid density. We predict the intermediate superfluid state where the condensate and localized bosons are present simultaneously. We find that interactions suppress localization and that with the increase of the boson density the system experiences a sharp delocalization crossover into a state where all bosons are delocalized. We map our results onto a 3D system of vortices in type II superconductors in the presence of columnar defects; the intermediate superfluid state maps to an intermediate vortex liquid where vortex liquid neighbors pinned vortices. We predict the depinning crossover within the vortex liquid and depinning induced vortex lattice-Bose glass melting.
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Affiliation(s)
- A V Lopatin
- Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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21
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Glyde HR, Albergamo F, Azuah RT, Bossy J, Fåk B. Dynamics of quantum liquids in confinement, theory and experiment. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2003; 12:63-68. [PMID: 15007681 DOI: 10.1140/epje/i2003-10024-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Liquid (4)He immersed in porous media such as aerogel, Vycor, and Geltech silica are excellent examples of bosons in disorder and confinement. Of special interest is the impact of disorder on Bose-Einstein condensation (BEC), on the elementary excitations of the superfluid and on their connection to the superfluid properties. Indeed, the modifications induced by disorder can be used to reveal the interdependence of BEC, the excitations and superfluidity. To date, the superfluid properties in porous media are much more completely documented than BEC or the excitations. In this paper, we review measurements of the excitations by neutron scattering, focusing particularly on their temperature dependence and the existence of phonon-roton excitations at higher temperatures. The weight of single excitation response at higher temperatures suggests the existence of localized BEC above the superfluid-normal transition temperature in porous media. We sketch several recent predictions made for BEC, the excitations, and the superfluid properties in disorder. Connections with other "Dirty Bose systems" are made.
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Affiliation(s)
- H R Glyde
- Department of Physics and Astronomy, University of Delaware, DE 19711, Newark, USA.
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22
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Lopatin AV, Vinokur VM. Thermodynamics of the superfluid dilute bose gas with disorder. PHYSICAL REVIEW LETTERS 2002; 88:235503. [PMID: 12059375 DOI: 10.1103/physrevlett.88.235503] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2001] [Indexed: 05/23/2023]
Abstract
We generalize the Beliaev-Popov diagrammatic technique for the problem of interacting dilute Bose gas with weak disorder. Averaging over disorder is implemented by the replica method. The low-energy asymptotic form of the Green function confirms that the low-energy excitations of the superfluid dirty-boson system are sound waves with velocity renormalized by the disorder and additional dissipation due to the impurity scattering. We find the thermodynamic potential and the superfluid density at any temperature below the superfluid transition temperature (but outside the Ginzburg region) and derive the phase diagram in temperature vs disorder plane.
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Affiliation(s)
- A V Lopatin
- Material Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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23
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Giorgini S, Pitaevskii L, Stringari S. Effects of disorder in a dilute Bose gas. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:12938-12944. [PMID: 10010205 DOI: 10.1103/physrevb.49.12938] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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24
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Singh KG, Rokhsar DS. Disordered bosons: Condensate and excitations. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:9013-9023. [PMID: 10009681 DOI: 10.1103/physrevb.49.9013] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Meng HF. Quantum theory of the two-dimensional interacting-boson system. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:1205-1210. [PMID: 10010428 DOI: 10.1103/physrevb.49.1205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Nisamaneephong P, Zhang L, Ma M. Gaussian theory of superfluid-Bose-glass phase transition. PHYSICAL REVIEW LETTERS 1993; 71:3830-3833. [PMID: 10055084 DOI: 10.1103/physrevlett.71.3830] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Kim K, Saam WF. Superfluid density in inhomogeneous 4He with applications to thin films. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:13735-13741. [PMID: 10007775 DOI: 10.1103/physrevb.48.13735] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Huang K, Meng HF. Superfluid helium in fully saturated porous media. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:6687-6690. [PMID: 10009233 DOI: 10.1103/physrevb.48.6687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Gold A. Superfluid-insulator transition in the Bogoliubov model. PHYSICAL REVIEW LETTERS 1993; 70:1563. [PMID: 10053325 DOI: 10.1103/physrevlett.70.1563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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