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arXiv · 0812.1332

Critical properties of a trapped interacting Bose gas

A. Bezett·P. B. Blakie
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Abstract

We develop a practical theoretical formalism for studying the critical properties of a trapped Bose-Einstein condensate using the projected Gross-Pitaevskii equation. We show that this approach allows us investigate the behavior of the correlation length, condensate mode and its number fluctuations about the critical point. Motivated by recent experiments [Science {\bf 315}, 1556 (2007)] we calculate the critical exponent for the correlation length, observe clear finite-size effects, and develop characteristic length scales to characterize the finite-size influences. We extend the Binder cumulant to the trapped system and discuss an experimental method for measuring number fluctuations.

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A. Bezett, P. B. Blakie. 2008-12-07. Critical properties of a trapped interacting Bose gas. https://doi.org/10.1103/physreva.79.033611

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