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Finite temperature correlation function for one-dimensional Quantum Ising model: the virial expansion

S. A. Reyes·A. M. Tsvelik
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Abstract

We rewrite the exact expression for the finite temperature two-point correlation function for the magnetization as a partition function of some field theory. This removes singularities and provides a convenient form to develop a virial expansion (the expansion in powers of soliton density).

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S. A. Reyes, A. M. Tsvelik. 2006-05-01. Finite temperature correlation function for one-dimensional Quantum Ising model: the virial expansion. https://doi.org/10.1103/physrevb.73.220405

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