Scaling of Static and Dynamical Properties of Random Anisotropy Magnets

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.