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Exact Correlation Amplitude for the S=1/2 Heisenberg Antiferromagnetic Chain

Ian Affleck
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Abstract

The exact amplitude for the asymptotic correlation function in the S=1/2 Heisenberg antiferromagnetic chain is determined: goes to (-1)^r delta^{ab}(ln r)^{1/2}/[(2 pi)^{3/2}r]. The behaviour of the correlation functions for small xxz anisotropy and the form of finite-size corrections to the correlation function are also analysed.

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Ian Affleck. 1998-02-20. Exact Correlation Amplitude for the S=1/2 Heisenberg Antiferromagnetic Chain. https://doi.org/10.1088/0305-4470%2F31%2F20%2F002

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