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arXiv:hep-lat/9404011 · Journal of Physics Condensed Matter

The critical region of the random-bond Ising model

A. L. Talapov, Щур Лев Николаевич

Published Oct 3, 1994• 25 citations
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Abstract

We describe results of the cluster algorithm special purpose processor simulations of the 2D Ising model with impurity bonds. We use large lattices with up to 10 6 spins to define critical temperature regions where both finite-size corrections and corrections to scaling are small. High-accuracy data unambiguously show an increase in the magnetization and magnetic susceptibility effective exponents beta and gamma , caused by impurities. The Mand chi -singularities become sharper, while the specific heat singularity is smoothed.

DOI
10.1088/0953-8984/6/40/020

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We describe results of the cluster algorithm special purpose processor simulations of the 2D Ising model with impurity bonds. We use large lattices with up to 10 6 spins to define critical temperature regions where both finite-size corrections and corrections to scaling are small. High-accuracy data unambiguously show an increase in the magnetization and magnetic susceptibility effective exponents beta and gamma , caused by impurities. The Mand chi -singularities become sharper, while the specific heat singularity is smoothed.
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