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Universality in Three Dimensional Random-Field Ground States

A. K. Hartmann·U. Nowak
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Abstract

We investigate the critical behavior of three-dimensional random-field Ising systems with both Gauss and bimodal distribution of random fields and additional the three-dimensional diluted Ising antiferromagnet in an external field. These models are expected to be in the same universality class. We use exact ground-state calculations with an integer optimization algorithm and by a finite-size scaling analysis we calculate the critical exponents nu, beta, and gamma-bar. While the random-field model with Gauss distribution of random fields and the diluted antiferromagnet appear to be in same universality class, the critical exponents of the random-field model with bimodal distribution of random fields seem to be significantly different.

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A. K. Hartmann, U. Nowak. 1998-09-18. Universality in Three Dimensional Random-Field Ground States. https://doi.org/10.1007/s100510050593

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