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Title: Nondiffusive phase spreading of a Bose-Einstein condensate at finite temperature

Abstract

We show that the phase of a condensate in a finite temperature gas spreads linearly in time at long times rather than in a diffusive way. This result is supported by classical field simulations, and analytical calculations which are generalized to the quantum case under the assumption of quantum ergodicity in the system. This superdiffusive behavior is intimately related to conservation of energy during the free evolution of the system and to fluctuations of energy in the prepared initial state.

Authors:
; ;  [1];  [2]
  1. Laboratoire Kastler Brossel, Ecole Normale Superieure, 24 Rue Lhomond, 75231 Paris Cedex 05 (France)
  2. (Poland)
Publication Date:
OSTI Identifier:
20982385
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.033616; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANALYTICAL SOLUTION; BOSE-EINSTEIN CONDENSATION; FLUCTUATIONS; SIMULATION; TEMPERATURE DEPENDENCE

Citation Formats

Sinatra, A., Castin, Y., Witkowska, E., and Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, 02-668 Warszawa. Nondiffusive phase spreading of a Bose-Einstein condensate at finite temperature. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.033616.
Sinatra, A., Castin, Y., Witkowska, E., & Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, 02-668 Warszawa. Nondiffusive phase spreading of a Bose-Einstein condensate at finite temperature. United States. doi:10.1103/PHYSREVA.75.033616.
Sinatra, A., Castin, Y., Witkowska, E., and Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, 02-668 Warszawa. Thu . "Nondiffusive phase spreading of a Bose-Einstein condensate at finite temperature". United States. doi:10.1103/PHYSREVA.75.033616.
@article{osti_20982385,
title = {Nondiffusive phase spreading of a Bose-Einstein condensate at finite temperature},
author = {Sinatra, A. and Castin, Y. and Witkowska, E. and Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, 02-668 Warszawa},
abstractNote = {We show that the phase of a condensate in a finite temperature gas spreads linearly in time at long times rather than in a diffusive way. This result is supported by classical field simulations, and analytical calculations which are generalized to the quantum case under the assumption of quantum ergodicity in the system. This superdiffusive behavior is intimately related to conservation of energy during the free evolution of the system and to fluctuations of energy in the prepared initial state.},
doi = {10.1103/PHYSREVA.75.033616},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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