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arXiv · 1404.1488

Gilbert damping in noncollinear ferromagnets

Zhe Yuan·Kjetil M. D. Hals·Yi Liu·Anton A. Starikov·Arne Brataas·Paul J. Kelly
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Abstract

The precession and damping of a collinear magnetization displaced from its equilibrium are described by the Landau-Lifshitz-Gilbert equation. For a noncollinear magnetization, it is not known how the damping should be described. We use first-principles scattering theory to investigate the damping in one-dimensional transverse domain walls (DWs) of the important ferromagnetic alloy Ni$_{80}$Fe$_{20}$ and interpret the results in terms of phenomenological models. The damping is found to depend not only on the magnetization texture but also on the specific dynamic modes of Bloch and Néel DWs. Even in the highly disordered Ni$_{80}$Fe$_{20}$ alloy, the damping is found to be remarkably nonlocal.

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Zhe Yuan, Kjetil M. D. Hals, Yi Liu, Anton A. Starikov, Arne Brataas, Paul J. Kelly. 2014-11-27. Gilbert damping in noncollinear ferromagnets. https://doi.org/10.1103/physrevlett.113.266603

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