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Thermally-Assisted Current-Driven Domain Wall Motion

R. A. Duine·A. S. Nunez·A. H. MacDonald
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Abstract

Starting from the stochastic Landau-Lifschitz-Gilbert equation, we derive Langevin equations that describe the nonzero-temperature dynamics of a rigid domain wall. We derive an expression for the average drift velocity of the domain wall as a function of the applied current, and find qualitative agreement with recent magnetic semiconductor experiments. Our model implies that at any nonzero temperature the average domain-wall velocity initially varies linearly with current, even in the absence of non-adiabatic spin torques.

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R. A. Duine, A. S. Nunez, A. H. MacDonald. 2006-07-25. Thermally-Assisted Current-Driven Domain Wall Motion. https://doi.org/10.1103/physrevlett.98.056605

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