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Critical Behavior of Anisotropic Heisenberg Mixed-Spin Chains in a Field

Toru Sakai·Shoji Yamamoto
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Abstract

We numerically investigate the critical behavior of the spin-(1,1/2) Heisenberg ferrimagnet with anisotropic exchange coupling in a magnetic field. A quantized magnetization plateau as a function of the field, appearing at a third of the saturated magnetization, is stable over whole the antiferromagnetic coupling region. The plateau vanishes in the ferromagnetic coupling region via the Kosterlitz-Thouless transition. Comparing the quantum and classical magnetization curves, we elucidate what are essential quantum effects.

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Toru Sakai, Shoji Yamamoto. 1999-05-15. Critical Behavior of Anisotropic Heisenberg Mixed-Spin Chains in a Field. https://doi.org/10.1103/physrevb.60.4053

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