arXiv:cond-mat/0404572 · Journal of Physics A Mathematical and General

Non-universal critical behaviour of two-dimensional Ising systems

K Minami, Masuo Suzuki

Published Nov 21, 1994• 13 citations

Abstract

Two conditions are derived for Ising models to show non-universal critical behaviour, namely, conditions concerning (i) logarithmic singularity of the specific heat and (ii) degeneracy of the ground state. These conditions are satisfied by the eight-vertex model, the Ashkin-Teller model, some Ising models with short- or long-range interactions and even Ising systems without the translational or rotational invariance.

DOI: 10.1088/0305-4470/27/22/008

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