Acta Physica Sinica

FREE-FERMION APPROXIMATE SOLUSION OF THE ISING MODEL ON UNION JACK LATTICE

WANG FU-GAO, HU JIA-ZHEN, 上海交通大学应用物理系凝聚态物理研究所,上海200030

Published Jan 1, 1993• 0 citations

Abstract

In this paper,the Ising model with two-body anisotropic interactions and three-body interactions on union Jack lattice is solved by free-fermion approximation. We have obtained its free energy, spontaneous magnetisation and the equation of critical points. When the interaction coefficients are simplified as in a square lattice Ising model, the same solusion as Onsager's is obtained.

DOI: 10.7498/aps.42.853

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