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arXiv · 1712.05052

Viscous dynamics of vortices in a ferromagnetic film

Derek Reitz·Anirban Ghosh·Oleg Tchernyshyov
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Abstract

We derive viscous forces for vortices in a thin-film ferromagnet. The viscous force acting on vortex $i$ is a linear superposition $\mathbf F_i = - \sum_{j} \hat{D}_{ij} \mathbf V_j$, where $\mathbf V_j$ is the velocity of vortex $j$. Thanks to the long-range nature of vortices, the mutual drag tensor $\hat{D}_{ij}$ is comparable in magnitude to the coefficient of self-drag $D_{ii}$.

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Derek Reitz, Anirban Ghosh, Oleg Tchernyshyov. 2017-12-13. Viscous dynamics of vortices in a ferromagnetic film. https://doi.org/10.1103/physrevb.97.054424

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