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Finite temperature density matrix and two-point correlations in the antiferromagnetic XXZ chain

Frank Göhmann·Nils P. Hasenclever·Alexander Seel
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Abstract

We derive finite temperature versions of integral formulae for the two-point correlation functions in the antiferromagnetic XXZ chain. The derivation is based on the summation of density matrix elements characterizing a finite chain segment of length $m$. On this occasion we also supply a proof of the basic integral formula for the density matrix presented in an earlier publication.

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Frank Göhmann, Nils P. Hasenclever, Alexander Seel. 2005-09-29. Finite temperature density matrix and two-point correlations in the antiferromagnetic XXZ chain. https://doi.org/10.1088/1742-5468%2F2005%2F10%2Fp10015

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