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Coherence length of an elongated condensate: a study by matter-wave interferometry

Mathilde Hugbart·Jocelyn Retter·Fabrice Gerbier·Andres Varon·Simon Richard·Joseph Thywissen·David Clement·Philippe Bouyer·Alain Aspect
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Abstract

We measure the spatial correlation function of Bose-Einstein condensates in the cross-over region between phase-coherent and strongly phase-fluctuating condensates. We observe the continuous path from a gaussian-like shape to an exponential-like shape characteristic of one-dimensional phase-fluctuations. The width of the spatial correlation function as a function of the temperature shows that the condensate coherence length undergoes no sharp transition between these two regimes.

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Mathilde Hugbart, Jocelyn Retter, Fabrice Gerbier, Andres Varon, Simon Richard, Joseph Thywissen, David Clement, Philippe Bouyer, Alain Aspect. 2005-01-19. Coherence length of an elongated condensate: a study by matter-wave interferometry. https://doi.org/10.1140/epjd%2Fe2005-00056-2

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