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Bogolyubov approximation for diagonal model of an interacting Bose gas

M. Corgini·D. P. Sankovich
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Abstract

We study, using the Bogolyubov approximation, the thermodynamic behaviour of a superstable Bose system whose energy operator in the second-quantized form contains a nonlinear expression in the occupation numbers operators. We prove that for all values of the chemical potential satisfying $μ> λ(0)$, where $λ(0)\leq 0$ is the lowest energy value, the system undergoes Bose--Einstein condensation.

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BibTeXRIS

M. Corgini, D. P. Sankovich. 2007-01-11. Bogolyubov approximation for diagonal model of an interacting Bose gas. https://doi.org/10.1016/j.physleta.2006.07.021

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