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arXiv · 1110.3201

Coherence properties of a 2D trapped Bose gas around the superfluid transition

T. Plisson·B. Allard·M. Holzmann·G. Salomon·Alain Aspect·Philippe Bouyer·Thomas Bourdel
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Abstract

We measure the momentum distribution of a 2D trapped Bose gas and observe the increase of the range of coherence around the Berezinskii-Kosterlitz-Thouless (BKT) transition. We quantitatively compare our observed profiles to both a Hartee-Fock mean-field theory and to quantum Monte-Carlo simulations. In the normal phase, we already observe a sharpening of the momentum distribution. This behavior is partially captured in a mean-field approach, in contrast to the physics of the BKT transition.

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T. Plisson, B. Allard, M. Holzmann, G. Salomon, Alain Aspect, Philippe Bouyer, Thomas Bourdel. 2011-10-14. Coherence properties of a 2D trapped Bose gas around the superfluid transition. https://doi.org/10.1103/physreva.84.061606

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