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Decay of Correlations in Fermi Systems at Non-zero Temperature

M. B. Hastings
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Abstract

The locality of correlation functions is considered for Fermi systems at non-zero temperature. We show that for all short-range, lattice Hamiltonians, the correlation function of any two fermionic operators decays exponentially with a correlation length which is of order the inverse temperature for small temperature. We discuss applications to numerical simulation of quantum systems at non-zero temperature.

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M. B. Hastings. 2004-06-16. Decay of Correlations in Fermi Systems at Non-zero Temperature. https://doi.org/10.1103/physrevlett.93.126402

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