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

Frank Göhmann·Andreas Klümper·Alexander Seel
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Abstract

We present an integral formula for the density matrix of a finite segment of the infinitely long spin-1/2 XXZ chain. This formula is valid for any temperature and any longitudinal magnetic field.

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Frank Göhmann, Andreas Klümper, Alexander Seel. 2004-12-02. Integral representation of the density matrix of the XXZ chain at finite temperatures. https://doi.org/10.1088/0305-4470%2F38%2F9%2F001

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