International Journal of Modern Physics B

Rigorous Estimates for Correlation Functions and Existence of Phase Transitions in Some Models of Interacting Bosons

M. Corgini, Дмитрий Петрович Санкович

Published Nov 10, 1997• 10 citations

Abstract

Using the so-called method of infrared bounds and a Roepstorff's inequality we obtain a lower bound for the amount of condensate and derive an upper bound for the anomalous average [Formula: see text] of Huang–Davies (HD) model. A lower bound for the static structure factor is also obtained. We generalize the HD model and prove the existence of Bose condensation for this kind of model systems. Finally we derived upper and lower bounds for correlation functions associated to a system of Fermi-particles interacting with a field of phonons.

DOI: 10.1142/s0217979297001635

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