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Temperature dependent spatial oscillations in the correlations of the XXZ spin chain

Klaus Fabricius·Andreas Klümper·Barry M. McCoy
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Abstract

We study the correlation $<σ^z_0σ^z_n>$ for the XXZ chain in the massless attractive (ferromagnetic) region at positive temperatures by means of a numerical study of the quantum transfer matrix. We find that there is a range of temperature where the behavior of the correlation for large separations is oscillatory with an incommensurate period which depends on temperature.

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Klaus Fabricius, Andreas Klümper, Barry M. McCoy. 1998-12-01. Temperature dependent spatial oscillations in the correlations of the XXZ spin chain. https://doi.org/10.1103/physrevlett.82.5365

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