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XX and Ising limits in integral formulae for finite temperature correlation functions of the XXZ chain

Frank Göhmann·Alexander Seel
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Abstract

We consider a multiple integral representation for a one-parameter generating function of the finite temperature $S^z$-$S^z$ correlation functions of the antiferromagnetic spin-1/2 XXZ chain in the XX limit and in the Ising limit. We show how in these limits the multiple integrals reduce to single integrals, thereby reproducing known results.

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Frank Göhmann, Alexander Seel. 2005-05-11. XX and Ising limits in integral formulae for finite temperature correlation functions of the XXZ chain. https://doi.org/10.1007/s11232-006-0012-x

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