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Spin-Reorientation Transition of Field-Induced Magnetic Ordering Phases in the Anisotropic Haldane System

Hiroshi Miyazaki·Tomohiko Hiwasa·Masataka Oko·Isao Harada
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Abstract

A possible spin-reorientation transition in field-induced magnetic ordering phases of the S=1 Haldane system with large easy-plane anisotropy is proposed, using an effective Lagrangian formalism as well as the density matrix renormalization group method. Such a spin-reorientation transition is predicted in the case where the applied magnetic field is inclined from the easy axis of the anisotropy. We point out that this transition has a close connection with a variation of the order parameter even at zero temperature, although it is different from a quantum analog of the so-called spin-flop transition proposed for the system having a strong easy axis anisotropy. In connection with a novel phase observed recently in the Haldane system at high fields, we discuss possible implications for the field-induced magnetic ordering.

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Hiroshi Miyazaki, Tomohiko Hiwasa, Masataka Oko, Isao Harada. 2006-07-13. Spin-Reorientation Transition of Field-Induced Magnetic Ordering Phases in the Anisotropic Haldane System. https://doi.org/10.1143/jpsj.75.094708

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