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The Critical Behaviour of Potts models with symmetry breaking fields

F. C. Alcaraz·J. C. Xavier
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Abstract

The $Q$-state Potts model in two dimensions in the presence of external magnetic fields is studied. For general $Q\geq3$ special choices of these magnetic fields produce effective models with smaller $Z(Q')$ symmetry $(Q'< Q)$. The phase diagram of these models and their critical behaviour are explored by conventional finite-size scaling and conformal invariance. The possibility of multicritical behavior, for finite values of the symmetry breaking fields, in the cases where $Q>4$ is also analysed. Our results indicate that for effective models with $Z(Q')$ symmetry $(Q'\leq4)$ the multicritical point occurs at zero field. This last result is also corroborated by Monte Carlo simulations.

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F. C. Alcaraz, J. C. Xavier. 1995-10-20. The Critical Behaviour of Potts models with symmetry breaking fields. https://doi.org/10.1088/0305-4470%2F29%2F13%2F009

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