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arXiv · 2407.21520

Scaling of Static and Dynamical Properties of Random Anisotropy Magnets

Dmitry A. Garanin·Eugene M. Chudnovsky
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Abstract

Recently observed scaling in the random-anisotropy model of amorphous or sintered ferromagnets is derived by an alternative method and extended for studying the dynamical properties in terms of the Landau-Lifshitz equations for spin blocks. Switching to the rescaled exchange and anisotropy constants allows one to investigate the dynamics by using a reduced number of variables, which greatly speeds up computations. The proposed dynamical scaling is applied to the problem of microwave absorption by a random anisotropy magnet. The equivalence of the rescaled model to the original atomic model is confirmed numerically. The method is proposed as a powerful tool in studying static and dynamic properties of systems with quenched randomness.

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Dmitry A. Garanin, Eugene M. Chudnovsky. 2024-07-31. Scaling of Static and Dynamical Properties of Random Anisotropy Magnets. https://doi.org/10.1209/0295-5075%2Fad8372

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