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arXiv · 2012.02482

Universality aspects of the 2d random-bond Ising and 3d Blume-Capel models

N. G. Fytas·P. E. Theodorakis
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Abstract

We report on large-scale Wang-Landau Monte Carlo simulations of the critical behavior of two spin models in two- (2d) and three-dimensions (3d), namely the 2d random-bond Ising model and the pure 3d Blume-Capel model at zero crystal-field coupling. The numerical data we obtain and the relevant finite-size scaling analysis provide clear answers regarding the universality aspects of both models. In particular, for the random-bond case of the 2d Ising model the theoretically predicted strong universality's hypothesis is verified, whereas for the second-order regime of the Blume-Capel model, the expected $d=3$ Ising universality is verified. Our study is facilitated by the combined use of the Wang-Landau algorithm and the critical energy subspace scheme, indicating that the proposed scheme is able to provide accurate results on the critical behavior of complex spin systems.

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N. G. Fytas, P. E. Theodorakis. 2020-12-04. Universality aspects of the 2d random-bond Ising and 3d Blume-Capel models. https://doi.org/10.1140/epjb/e2012-30705-x

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