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arXiv:cond-mat/0504672 · Journal of Physics A Mathematical and General

Fluctuations of the Fermi condensate in ideal gases

Dragoş-Victor Anghel, Oleg Fefelov, Y M Galperin

Published Oct 12, 2005• 6 citations
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Abstract

We calculate numerically and analytically the grandcanonical fluctuation of the number of particles both, in the fermionic condensate and above it, for ideal Fermi systems of constant density of states. We compare the canonical fluctuations, obtained from the equivalent Bose condensate fluctuation, with the grandcanonical fermionic calculation. The fluctuations of the condensate are almost the same in the two ensembles with a small correction coming from the total particle number fluctuation in the grandcanonical ensemble. On the other hand, well below the condensation temperature, the number of particles above the condensate and its fluctuation are insensitive to the choice of ensemble.

DOI
10.1088/0305-4470/38/43/001

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