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arXiv:cond-mat/0412062 · Journal of Physics A Mathematical and General

Integral representation of the density matrix of the XXZ chain at finite temperatures

Frank Göhmann, Andreas Klümper, Alexander Seel

Published Feb 17, 2005• 100 citations
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Abstract

We present an integral formula for the density matrix of a finite segment of the infinitely long spin- XXZ chain. This formula is valid for any temperature and any longitudinal magnetic field.
DOI
10.1088/0305-4470/38/9/001

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