Journal of the Physical Society of Japan

First-Order Phase Transition in theS=1Quantum Spin Chain with Partial Integrability

Ryutaro Sato, Yasuhiro Akutsu

Published Jul 15, 1996• 17 citations

Abstract

The zero-temperature magnetization curve of the S =1 antiferromagnetic XXZ chain with partial integrability is studied by the Bethe ansatz, combined with a numerical renormalization-group method. We find a magnetic first-order phase transition; the magnetization curve shows a discontinuity at a critical field h c . Due to the partial integrability, the low-field curve and the high-field curve each correspond to a part of the magnetization curve of the \(S=\frac12\)XXZ chain. We conclude that the obtained magnetization curve is exact in the whole range of the magnetic field.

DOI: 10.1143/jpsj.65.1885

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