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Long-distance asymptotics of spin-spin correlation functions for the XXZ spin chain

Sergei Lukyanov·Veronique Terras
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Abstract

We study asymptotic expansions of spin-spin correlation functions for the XXZ Heisenberg chain in the critical regime. We use the fact that the long-distance effects can be described by the Gaussian conformal field theory. Comparing exact results for form factors in the XYZ and sine-Gordon models, we determine correlation amplitudes for the leading and main sub-leading terms in the asymptotic expansions of spin-spin correlation functions. We also study the isotropic (XXX) limit of these expansions.

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Sergei Lukyanov, Veronique Terras. 2002-06-11. Long-distance asymptotics of spin-spin correlation functions for the XXZ spin chain. https://doi.org/10.1016/s0550-3213(02)01141-0

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