Journal of Physics C Solid State Physics

Low-temperature expansions for Ising models with four-spin interactions

J. Oitmaa

Published Jan 21, 1974• 14 citations

Abstract

Low-temperature series for the spontaneous magnetization are derived for two Ising models with four-spin interactions-(i) a model studied previously by the author using high temperature series, (ii) a model equivalent to Baxter's (1973) eight-vertex model. In the former case the exponent beta appears to remain constant at 1/8, independent of J 4 , the strength of the four-spin interaction; for the eight-vertex model beta varies continuously with J 4 as expected.

DOI: 10.1088/0022-3719/7/2/017

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