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arXiv · 0907.2867

Influence of magnetic viscosity on domain wall dynamics under spin-polarized currents

Joo-Von Kim·Capucine Burrowes
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Abstract

We present a theoretical study of the influence of magnetic viscosity on current-driven domain wall dynamics. In particular we examine how domain wall depinning transitions, driven by thermal activation, are influenced by the adiabatic and nonadiabatic spin-torques. We find the Arrhenius law that describes the transition rate for activation over a single energy barrier remains applicable under currents but with a current-dependent barrier height. We show that the effective energy barrier is dominated by a linear current dependence under usual experimental conditions, with a variation that depends only on the nonadiabatic spin torque coefficient beta.

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Joo-Von Kim, Capucine Burrowes. 2009-07-16. Influence of magnetic viscosity on domain wall dynamics under spin-polarized currents. https://doi.org/10.1103/physrevb.80.214424

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