Anomalous fluctuations of two-dimensional Bose-Einstein condensates
نویسندگان
چکیده
We investigate the particle-number fluctuations of condensate due to collective excitations for trapped two-dimensional (2D) and quasi-2D Bose gases at low temperature. We show that the fluctuations of the condensate are proportional to the square of the total particle number of the system. For a quasi-2D Bose gas the fluctuations are also proportional to the square root of the trapping frequency in the strong confining direction. This anomalous behavior of the condensate fluctuations can be tested by the present-day experiment based on two-dimensional Bose-Einstein condensates. PACS number(s): 03.75.Fi, 05.30.Jp, 67.40.Db
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