Two-dimensional Dilute Ising Models: Defect Lines and the Universality of the Critical Exponent ν

Ferenc Szalma; Ferenc Igloi

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Two-dimensional Dilute Ising Models: Defect Lines and the Universality of the Critical Exponent ν

Ferenc Szalma·Ferenc Igloi

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Abstract

We consider two-dimensional Ising models with randomly distributed ferromagnetic bonds and study the local critical behavior at defect lines by extensive Monte Carlo simulations. Both for ladder and chain type defects, non-universal critical behavior is observed: the critical exponent of the defect magnetization is found to be a continuous function of the strength of the defect coupling. Analyzing corresponding stability conditions, we obtain new evidence that the critical exponent $ν$ of the bulk correlation length of the random Ising model does not depend on dilution, i.e. $ν=1$.

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Ferenc Szalma, Ferenc Igloi. 1999-01-05. Two-dimensional Dilute Ising Models: Defect Lines and the Universality of the Critical Exponent ν. https://arxiv.org/abs/cond-mat/9901026

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