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arXiv · 1105.4148

Magnetization Dissipation in the Ferromagnetic Semiconductor (Ga,Mn)As

Kjetil M. D. Hals·Arne Brataas
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Abstract

We compute the Gilbert damping in (Ga,Mn)As based on the scattering theory of magnetization relaxation. The disorder scattering is included non-perturbatively. In the clean limit, the spin-pumping from the localized d-electrons to the itinerant holes dominates the relaxation processes. In the diffusive regime, the breathing Fermi-surface effect is balanced by the effects of interband scattering, which cause the Gilbert damping constant to saturate at around 0.005. In small samples, the system shape induces a large anisotropy in the Gilbert damping.

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Kjetil M. D. Hals, Arne Brataas. 2011-05-20. Magnetization Dissipation in the Ferromagnetic Semiconductor (Ga,Mn)As. https://doi.org/10.1103/physrevb.84.104404

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