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Anomalous condensate fluctuations in strongly interacting superfluids

F. Meier·W. Zwerger
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Abstract

We show that the condensate occupation of a superfluid Bose liquid quite generally exhibits anomalously large fluctuations at finite temperatures. In three dimensions, the variance scales like T^2 V^{4/3} at low T, generalizing the result obtained by Giorgini, Pitaevskii, and Stringari for a weakly interacting Bose gas. In two dimensions there is only a quasicondensate, and the fluctuations are of the same order as the mean value.

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F. Meier, W. Zwerger. 1999-08-12. Anomalous condensate fluctuations in strongly interacting superfluids. https://doi.org/10.1103/physreva.60.5133

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