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Anomalous fluctuations of two-dimensional Bose-Einstein condensates

Hongwei Xiong·Shujuan Liu·Guoxiang Huang
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Abstract

We investigate the particle-number fluctuations due to the collective excitations created in a two-dimensional (2D) and a quasi-2D Bose-Einstein condensates (BECs) at low temperature. We find that the fluctuations display an anomalous behavior, i. e. for the 2D BEC they are proportional to $N^2$, where $N$ is the total number of particles. For the quasi-2D BEC, the particle-number fluctuations are proportional not only to $N^2$ but also to the square root of the trapping frequency in the strongly-confined direction.

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Hongwei Xiong, Shujuan Liu, Guoxiang Huang. 2003-04-25. Anomalous fluctuations of two-dimensional Bose-Einstein condensates. https://doi.org/10.1103/physreva.67.055601

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