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Universal Pulse Shape Scaling Function and Exponents: A Critical Test for Avalanche Models applied to Barkhausen Noise

Amit P. Mehta·Andrea C. Mills·Karin Dahmen·James P. Sethna
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Abstract

In order to test if the universal aspects of Barkhausen noise in magnetic materials can be predicted from recent variants of the non-equilibrium zero temperature Random Field Ising Model (RFIM), we perform a quantitative study of the universal scaling function derived from the Barkhausen pulse shape in simulations and experiment. Through data collapses and scaling relations we determine the critical exponents $τ$ and $1/σνz$ in both simulation and experiment. Although we find agreement in the critical exponents, we find differences between theoretical and experimental pulse shape scaling functions as well as between different experiments.

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Amit P. Mehta, Andrea C. Mills, Karin Dahmen, James P. Sethna. 2001-12-08. Universal Pulse Shape Scaling Function and Exponents: A Critical Test for Avalanche Models applied to Barkhausen Noise. https://doi.org/10.1103/physreve.65.046139

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