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arXiv · 1610.09006

On the Semi-Classical Limit of Scalar Products of the XXZ Spin Chain

Yunfeng Jiang·Joren Brunekreef
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Abstract

We study the scalar products between Bethe states in the XXZ spin chain with anisotropy $|Δ|>1$ in the semi-classical limit where the length of the spin chain and the number of magnons tend to infinity with their ratio kept finite and fixed. Our method is a natural yet non-trivial generalization of similar methods developed for the XXX spin chain. The final result can be written in a compact form as a contour integral in terms of Faddeev's quantum dilogarithm function, which in the isotropic limit reduces to the classical dilogarithm function.

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Yunfeng Jiang, Joren Brunekreef. 2017-03-20. On the Semi-Classical Limit of Scalar Products of the XXZ Spin Chain. https://doi.org/10.1007/jhep03(2017)012

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