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Exact results for the sigma^z two-point function of the XXZ chain at Delta=1/2

N. Kitanine·J. M. Maillet·N. A. Slavnov·V. Terras
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Abstract

We propose a new multiple integral representation for the correlation function of the XXZ spin-1/2 Heisenberg chain in the disordered regime. We show that for Delta=1/2 the integrals can be separated and computed exactly. As an example we give the explicit results up to the lattice distance m=8. It turns out that the answer is given as integer numbers divided by 2^[(m+1)^2].

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N. Kitanine, J. M. Maillet, N. A. Slavnov, V. Terras. 2005-06-14. Exact results for the sigma^z two-point function of the XXZ chain at Delta=1/2. https://doi.org/10.1088/1742-5468%2F2005%2F09%2Fl09002

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