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Finite-size scaling for the S=1/2 Heisenberg Antiferromagnetic Chain

Victor Barzykin·Ian Affleck
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Abstract

Corrections to the asymptotic correlation function in a Heisenberg spin-1/2 antiferromagnetic spin chain are known to vanish slowly (logarithmically) as a function of the distance r or the chain size L. This leads to significant differences with numerical results. We calculate the sub-leading logarithmic corrections to the finite-size correlation function, using renormalization group improved perturbation theory, and compare the result with numerical data.

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Victor Barzykin, Ian Affleck. 1998-10-07. Finite-size scaling for the S=1/2 Heisenberg Antiferromagnetic Chain. https://doi.org/10.1088/0305-4470%2F32%2F6%2F001

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