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.
@article{arxiv.cond-mat/0302336,
title = {Magnetic Susceptibility of an integrable anisotropic spin ladder system},
author = {A. P. Tonel and S. R. Dahmen and A. Foerster and A. L. Malvezzi},
journal= {arXiv preprint arXiv:cond-mat/0302336},
year = {2007}
}
Comments
12 pages, 12 figures included, submitted to Phys. Rev. B