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physica status solidi (b)

An Effective‐Field Theory of Mixed Ising Spin Systems in Transverse Fields

T. Kaneyoshi, Enaldo F. Sarmento, I. P. Fittipaldi

Published Nov 1, 1988• 40 citations
Publisher

Abstract

Abstract An effective‐field theory is proposed and used to derive the thermodynamic properties of the mixed Ising spin system consisting of spin‐½ and spin‐1 with different transverse fields. The effects of transverse fields on the critical behavior and the magnetization curves are studied. It is shown that the present formalism, in spite of its simplicity, yields results which represent a remarkable improvement on the mean‐field treatment.

DOI
10.1002/pssb.2221500129

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