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arXiv · 1002.0207

Spin relaxation torque in metallic ferromagnets

Noriyuki Nakabayashi·Akihito Takeuchi·Kazuhiro Hosono·Katsuhisa Taguchi·Gen Tatara
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Abstract

Spin relaxation torque ${\cal T}$ in uniform metallic ferromagnets with the spin-orbit interaction arising from random impurities is calculated microscopically. ${\cal T}$ is shown to be written by spatial derivatives of the electric field, but is not always given as a divergence of a torque dipole density. The result is due to the fast dissipation of the orbital angular momentum, and thus a conserving spin current cannot be defined. It is discussed that the $\beta$ term in the spin transfer torque can also be asymmetric.

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Noriyuki Nakabayashi, Akihito Takeuchi, Kazuhiro Hosono, Katsuhisa Taguchi, Gen Tatara. 2010-02-01. Spin relaxation torque in metallic ferromagnets. https://doi.org/10.1103/physrevb.82.014403

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