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Anomalous particle-number fluctuations in a three-dimensional interacting Bose-Einstein condensate

Shujuan Liu·Hongwei Xiong·Guoxiang Huang·Zhijun Xu
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Abstract

The particle-number fluctuations originated from collective excitations are investigated for a three-dimensional, repulsively interacting Bose-Einstein condensate (BEC) confined in a harmonic trap. The contribution due to the quantum depletion of the condensate is calculated and the explicit expression of the coefficient in the formulas denoting the particle-number fluctuations is given. The results show that the particle-number fluctuations of the condensate follow the law $<δN_0^2> \sim N^{22/15}$ and the fluctuations vanish when temperature approaches to the BEC critical temperature.

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Shujuan Liu, Hongwei Xiong, Guoxiang Huang, Zhijun Xu. 2004-01-08. Anomalous particle-number fluctuations in a three-dimensional interacting Bose-Einstein condensate. https://doi.org/10.1103/physreva.68.065601

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