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Integral equations for thermodynamics of the osp(1|2s) integrable spin chain

Zengo Tsuboi
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Abstract

We propose a system of nonlinear integral equations (NLIE), which gives the free energy of the osp(1|2s) integrable spin chain at finite temperatures. In contrast with usual thermodynamic Bethe ansatz equations, our new NLIE contain only a finite number of unknown functions. On deriving NLIE, we use our osp(1|2s) version of the T-system and the quantum transfer matrix method. Based on our NLIE, we also calculate the high temperature expansion of the free energy and the specific heat.

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Zengo Tsuboi. 2002-09-13. Integral equations for thermodynamics of the osp(1|2s) integrable spin chain. https://doi.org/10.1016/s0370-2693(02)02463-2

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