Integral Absorption of Microwave Power by Random-Anisotropy Magnets

Abstract

We study analytically and numerically on lattices containing $10^5$ spins, the integral absorption of microwaves by a random-anisotropy magnet, $\int d\omega P(\omega )$. It scales as $D_R^2/J$ on the random-anisotropy strength $D_R$ and the strength of the ferromagnetic exchange $J$ in low-anisotropy amorphous magnetic materials. At high anisotropy and in low-anisotropy materials sintered of sufficiently large ferromagnetic grains, the integral power scales linearly on $D_R$. The maximum bandwidth, combined with the maximum absorption power, is achieved when the amorphous structure factor, or grain size, is of an order of the domain wall thickness in a conventional ferromagnet that is of the order of $(J/D_R{)}^{1/2}$ lattice spacings.

9 pages, 5 figure captions

References in corpus (4)

• Experimental and Numerical Understanding of Localized Spin Wave Mode Behavior in Broadly Tunable Spatially Complex Magnetic Configurations
• Nonlinear and Thermal Effects in the Absorption of Microwaves by Random Magnets
• Random Anisotropy Magnet at Finite Temperature
• Localized Spin-Wave Modes and Microwave Absorption in Random-Anisotropy Ferromagnets

Cited by in corpus (4)

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