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arXiv:1510.03215 · Journal of Statistical Physics

Correlation Inequalities for the Quantum XY Model

Costanza Benassi, Benjamin Lees, Daniel Ueltschi

Published Jul 11, 2016• 5 citations
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Abstract

We show the positivity or negativity of truncated correlation functions in the quantum XY model with spin 1/2 (at any temperature) and spin 1 (in the ground state). These Griffiths-Ginibre inequalities of the second kind generalise an earlier result of Gallavotti.
DOI
10.1007/s10955-016-1580-2

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