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Reproducible noise in a macroscopic system: magnetic avalanches in Perminvar

J. S. Urbach·R. C. Madison·J. T. Markert
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Abstract

A study of magnetic avalanches in Perminvar, an Fe-Ni-Co alloy, shows that some avalanches are almost exactly reproducible from one magnetic field cycle to the next, while others show significant variability. Averaging over many cycles produces a fingerprint reflecting the reproducibility of the noise. The fingerprint is not strongly temperature or driving-rate dependent, indicating that the variability is a consequence of dynamical effects. We also find that the slope of the cycle-averaged magnetization, d /dH, is correlated with the cycle-to-cycle variations in magnetization, suggesting an analogy with the fluctuation-dissipation relationship from equilibrium thermodynamics.

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J. S. Urbach, R. C. Madison, J. T. Markert. 1995-08-17. Reproducible noise in a macroscopic system: magnetic avalanches in Perminvar. https://arxiv.org/abs/adap-org/9508005

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