• Corpus ID: 118195020

Universality and non-universality in the Ashkin-Teller model

  title={Universality and non-universality in the Ashkin-Teller model},
  author={Alessandro Giuliani},
  journal={arXiv: Statistical Mechanics},
  • A. Giuliani
  • Published 1 December 2004
  • Physics
  • arXiv: Statistical Mechanics
The Ashkin-Teller model can be formulated as a pair of 2D Ising models, interacting via a four-spin interaction. I consider the case of weak anisotropy (slight a-symmetry between the two Ising layers) and weak coupling. I show that the system admits two critical temperatures whose difference varies continuously with the strength of the coupling, scaling with an anomalous exponent as one let the a-symmetry parameter go to zero. The specific heat diverges logarithmically at the critical points… 



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