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Universal temperature dependence of the magnetization of gapped spin chains

Yoshitaka Maeda·Chisa Hotta·Masaki Oshikawa
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Abstract

Temperature dependence of the magnetization of the Haldane spin chain at finite magnetic field is analyzed systematically. Quantum Monte Carlo data indicates a clear minimum of magnetization as a function of temperature in the gapless regime. On the basis of the Tomonaga-Luttinger liquid theory, we argue that this minimum is rather universal and can be observed for general axially symmetric quasi-one-dimensional spin systems. Our argument is confirmed by the magnetic-field dependence of the spin-wave velocity obtained numerically. One can estimate a magnitude of the gap of any such systems by fitting the experimental data with the magnetization minimum.

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Yoshitaka Maeda, Chisa Hotta, Masaki Oshikawa. 2007-03-27. Universal temperature dependence of the magnetization of gapped spin chains. https://doi.org/10.1103/physrevlett.99.057205

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