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Momentum Spectroscopy of Phase Fluctuations of an Elongated Bose-Einstein Condensate

A. Aspect·S. Richard·F. Gerbier·M. Hugbart·J. Retter·J. Thywissen·P. Bouyer
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Abstract

We have measured the momentum distribution of an elongated BEC (aspect ratio of 152), for temperatures below the critical temperature. The corresponding coherence length is significantly smaller than the condensate length in a wide range of temperature, in quantitative agreement with theoretical predictions. The Lorentzian shape of the momentum spectrum supports the image of a phase fluctuating quasicondensate.

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A. Aspect, S. Richard, F. Gerbier, M. Hugbart, J. Retter, J. Thywissen, P. Bouyer. 2003-09-11. Momentum Spectroscopy of Phase Fluctuations of an Elongated Bose-Einstein Condensate. https://doi.org/10.1142/9789812703002_0018

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