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arXiv · 1503.08505

Geometric expansion of the log-partition function of the anisotropic Heisenberg model

Daniel Gandolfo·Suren Poghosyan·Jean Ruiz
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Abstract

We study the asymptotic expansion of the log-partition function of the anisotropic Heisenberg model in a bounded domain as this domain is dilated to infinity. Using the Ginibre's representation of the anisotropic Heisenberg model as a gas of interacting trajectories of a compound Poisson process we find all the non-decreasing terms of this expansion. They are given explicitly in terms of functional integrals. As the main technical tool we use the cluster expansion method.

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Daniel Gandolfo, Suren Poghosyan, Jean Ruiz. 2015-03-29. Geometric expansion of the log-partition function of the anisotropic Heisenberg model. https://doi.org/10.1063/1.4931478

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