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Journal of the Physical Society of Japan

Bosonic Quantum Spherical Model for theXYMagnet

Yu‐qiang Ma

Published Jul 15, 1999• 1 citation
Publisher

Abstract

We propose a bosonic spherical model to investigate the phase transition and critical behaviors of the quantum X Y ferromagnet. We calculate the low-temperature thermodynamics and critical exponents near the phase transition, and compare with the results of the conventional spherical model in the spin space. The possibilities of the existence of the ordered phase of the system are examined for d < 2 and d =3, respectively. The effects of the exchange anisotropy on the phase transition temperature are also discussed.

DOI
10.1143/jpsj.68.2361

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