Phase transition in the 2d random Potts model in the large-q limit

J-Ch. Angles d'Auriac; F. Igloi

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Phase transition in the 2d random Potts model in the large-q limit

J-Ch. Angles d'Auriac·F. Igloi

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Abstract

Phase transition in the two-dimensional $q$-state Potts model with random ferromagnetic couplings in the large-q limit is conjectured to be described by the isotropic version of the infinite randomness fixed point of the random transverse-field Ising spin chain. This is supported by extensive numerical studies with a combinatorial optimization algorithm giving estimates for the critical exponents in accordance with the conjectured values: $β=(3-\sqrt{5})/4$, $β_s=1/2$ and $ν=1$. The specific heat has a logarithmic singularity, but at the transition point there are very strong sample-to-sample fluctuations. Discretized randomness results in discontinuities in the internal energy.

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BibTeX RIS

J-Ch. Angles d'Auriac, F. Igloi. 2002-11-25. Phase transition in the 2d random Potts model in the large-q limit. https://arxiv.org/abs/cond-mat/0211543

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