Second cluster integral from the spectrum of an infinite XXZ spin chain

P. N. Bibikov

doi:10.1016/j.aop.2014.12.020

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arXiv · 1408.4586

Second cluster integral from the spectrum of an infinite XXZ spin chain

P. N. Bibikov

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Abstract

First and second terms of the low-temperature cluster expansion for the free energy density of a magnetically polarized $XXZ$ spin chain is obtained within the propagator approach suggested by E. W. Montroll and J. C. Ward. All the calculations employ only one- and two-magnon infinite-chain spectrums. In the $XXX$-point the result reproduces the well known S. Katsura's formula obtained 50 years ago by finite-chain calculations.

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P. N. Bibikov. 2014-08-20. Second cluster integral from the spectrum of an infinite XXZ spin chain. https://doi.org/10.1016/j.aop.2014.12.020

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