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arXiv · 1201.0990

Quantum Kinetic Theory of Current-Induced Torques in Rashba Ferromagnets

D. A. Pesin·A. H. MacDonald
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Abstract

Motivated by recent experimental studies of thin-film devices containing a single ferromagnetic layer, we develop a quantum kinetic theory of current-induced magnetic torques in Rashba-model ferromagnets. We find that current-induced spin-densities that are responsible for the switching behavior are due most essentially to spin-dependent quasiparticle lifetimes and derive analytic expressions for relevant limits of a simple model. Quantitative model parameter estimates suggest that spin-orbit coupling in the adjacent metal normal magnetic layer plays an essential role in the strength of the switching effect.

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D. A. Pesin, A. H. MacDonald. 2012-01-04. Quantum Kinetic Theory of Current-Induced Torques in Rashba Ferromagnets. https://doi.org/10.1103/physrevb.86.014416

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