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Linear Response in the s.c. Bogolyubov model of Bose-Einstein Condensation

L. Banyai·M. A. Bundaru·P. Gartner
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Abstract

We discuss the linear response of the Bogolyubov theory of a weakly interacting Bose gas below the critical temperature. The specific aspects, due to induced perturbation terms in the self-consistent treatment are discussed in detail. We show that Bogolyubov's model having a gap-less equilibrium spectrum nevertheless gives rise to an effective susceptibility which does not satisfy the super-fluidity criterion of Hohenberg and Martin.

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BibTeXRIS

L. Banyai, M. A. Bundaru, P. Gartner. 2004-07-16. Linear Response in the s.c. Bogolyubov model of Bose-Einstein Condensation. https://arxiv.org/abs/cond-mat/0407426

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