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Non-Universal Critical Behaviour of Two-Dimensional Ising Systems

Kazuhiko Minami·Masuo Suzuki
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Abstract

Two conditions are derived for Ising models to show non-universal critical behaviour, namely conditions concerning 1) logarithmic singularity of the specific heat and 2) degeneracy of the ground state. These conditions are satisfied with 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 the rotational invariance.

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Kazuhiko Minami, Masuo Suzuki. 2004-04-23. Non-Universal Critical Behaviour of Two-Dimensional Ising Systems. https://doi.org/10.1088/0305-4470%2F27%2F22%2F008

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