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Condensate statistics in interacting Bose gases: exact results

Iacopo Carusotto·Yvan Castin
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Abstract

Recently, a Quantum Monte Carlo method alternative to the Path Integral Monte Carlo method was developed for the numerical solution of the N-boson problem; it is based on the stochastic evolution of classical fields. Here we apply it to obtain exact results for the occupation statistics of the condensate mode in a weakly interacting trapped one-dimensional Bose gas. The temperature is varied across the critical region down to temperatures lower than the trap level spacing. We verify that the number-conserving Bogoliubov theory gives accurate predictions provided that the non-condensed fraction is small.

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Iacopo Carusotto, Yvan Castin. 2002-09-19. Condensate statistics in interacting Bose gases: exact results. https://doi.org/10.1103/physrevlett.90.030401

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