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arXiv · hep-th/9212125

Low-Temperature Thermodynamics of $A^{(2)}_2$ and su(3)-invariant Spin Chains

Luca Mezincescu·Rafael I. Nepomechie·P. K. Townsend·A. M. Tsvelik
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Abstract

We formulate the thermodynamic Bethe Ansatz (TBA) equations for the closed (periodic boundary conditions) $A^{(2)}_2$ quantum spin chain in an external magnetic field, in the (noncritical) regime where the anisotropy parameter $η$ is real. In the limit $η\to 0$, we recover the TBA equations of the antiferromagnetic su(3)-invariant chain in the fundamental representation. We solve these equations for low temperature and small field, and calculate the specific heat and magnetic susceptibility.

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Luca Mezincescu, Rafael I. Nepomechie, P. K. Townsend, A. M. Tsvelik. 1992-12-21. Low-Temperature Thermodynamics of $A^{(2)}_2$ and su(3)-invariant Spin Chains. https://doi.org/10.1016/0550-3213(93)90006-b

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