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Antiferromagnetic Zigzag Spin Chain in Magnetic Fields at Finite Temperatures

Nobuya Maeshima·Kouichi Okunishi
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Abstract

We study thermodynamic behaviors of the antiferromagnetic zigzag spin chain in magnetic fields, using the density-matrix renormalization group method for the quantum transfer matrix. We focus on the thermodynamics of the system near the critical fields in the ground-state magnetization process($M$-$H$ curve): the saturation field, the lower critical field associated with excitation gap, and the field at the middle-field cusp singularity. We calculate magnetization, susceptibility and specific heat of the zigzag chain in magnetic fields at finite temperatures, and then discuss how the calculated quantities reflect the low-lying excitations of the system related with the critical behaviors in the $M$-$H$ curve.

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Nobuya Maeshima, Kouichi Okunishi. 2000-04-14. Antiferromagnetic Zigzag Spin Chain in Magnetic Fields at Finite Temperatures. https://doi.org/10.1103/physrevb.62.934

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