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Magnetic Susceptibility of an integrable anisotropic spin ladder system

A. P. Tonel·S. R. Dahmen·A. Foerster·A. L. Malvezzi
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Abstract

We investigate the thermodynamics of a spin ladder model which possesses a free parameter besides the rung and leg couplings. The model is exactly solved by the Bethe Ansatz and exhibits a phase transition between a gapped and a gapless spin excitation spectrum. The magnetic susceptibility is obtained numerically and its dependence on the anisotropy parameter is determined. A connection with the compounds KCuCl3, Cu2(C5H12N2)2Cl4 and (C5H12N)2CuBr4 in the strong coupling regime is made and our results for the magnetic susceptibility fit the experimental data remarkably well.

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A. P. Tonel, S. R. Dahmen, A. Foerster, A. L. Malvezzi. 2003-02-17. Magnetic Susceptibility of an integrable anisotropic spin ladder system. https://doi.org/10.1209/epl%2Fi2003-00144-3

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