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Disorder-Induced Critical Phenomena in Hysteresis: A Numerical Scaling Analysis

Olga Perkovic·Karin A. Dahmen·James P. Sethna
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Abstract

Experimental systems with a first order phase transition will often exhibit hysteresis when out of equilibrium. If defects are present, the hysteresis loop can have different shapes: with small disorder the hysteresis loop has a macroscopic jump, while for large disorder the hysteresis loop is smooth. The transition between these two shapes is critical, with diverging length scales and power laws. We simulate such a system with the zero temperature random field Ising model, in 2, 3, 4, 5, 7, and 9 dimensions, with systems of up to 1000^3 spins, and find the critical exponents from scaling collapses of several measurements. The numerical results agree well with the analytical predictions from a renormalization group calculation.

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Olga Perkovic, Karin A. Dahmen, James P. Sethna. 1996-09-06. Disorder-Induced Critical Phenomena in Hysteresis: A Numerical Scaling Analysis. https://arxiv.org/abs/cond-mat/9609072

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