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The anisotropic Ashkin-Teller model: a renormalization group study

C. G. Bezerra·A. M. Mariz·J. M. de Araujo·F. A. da Costa
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Abstract

The two-dimensional ferromagnetic anisotropic Ashkin-Teller model is investigated through a real-space renormalization-group approach. The critical frontier, separating five distinct phases, recover all the known exacts results for the square lattice. The correlation length $(ν_T)$ and crossover $(ϕ)$ critical exponents are also calculated. With the only exception of the four-state Potts critical point, the entire phase diagram belongs to the Ising universality class.

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C. G. Bezerra, A. M. Mariz, J. M. de Araujo, F. A. da Costa. 2001-02-05. The anisotropic Ashkin-Teller model: a renormalization group study. https://doi.org/10.1016/s0378-4371(00)00568-9

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