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arXiv · 0905.4170

Scattering Theory of Charge-Current Induced Magnetization Dynamics

Kjetil M. D. Hals·Arne Brataas·Yaroslav Tserkovnyak
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Abstract

In ferromagnets, charge currents can excite magnons via the spin-orbit coupling. We develop a novel and general scattering theory of charge current induced macrospin magnetization torques in normal metal$|$ferromagnet$|$normal metal layers. We apply the formalism to a dirty GaAs$|$(Ga,Mn)As$|$GaAs system. By computing the charge current induced magnetization torques and solving the Landau-Lifshitz-Gilbert equation, we find magnetization switching for current densities as low as $ 5\times 10^{6}$~A/cm$^2$. Our results are in agreement with a recent experimental observation of charge-current induced magnetization switching in (Ga,Mn)As.

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Kjetil M. D. Hals, Arne Brataas, Yaroslav Tserkovnyak. 2010-06-09. Scattering Theory of Charge-Current Induced Magnetization Dynamics. https://doi.org/10.1209/0295-5075%2F90%2F47002

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