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Momentum spectroscopy of 1D phase fluctuations in Bose-Einstein condensates

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

We measure the axial momentum distribution of Bose-Einstein condensates with an aspect ratio of 152 using Bragg spectroscopy. We observe the Lorentzian momentum distribution characteristic of one-dimensional phase fluctuations. The temperature dependence of the width of this distribution provides a quantitative test of quasi-condensate theory. In addition, we observe a condensate length consistent with the absence of density fluctuations, even when phase fluctuations are large.

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S. Richard, F. Gerbier, J. H. Thywissen, M. Hugbart, P. Bouyer, A. Aspect. 2003-03-07. Momentum spectroscopy of 1D phase fluctuations in Bose-Einstein condensates. https://doi.org/10.1103/physrevlett.91.010405

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