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arXiv · 1701.08357

Current-driven skyrmion dynamics in disordered films

Joo-Von Kim·Myoung-Woo Yoo
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Abstract

A theoretical study of the current-driven dynamics of magnetic skyrmions in disordered perpendicularly-magnetized ultrathin films is presented. The disorder is simulated as a granular structure in which the local anisotropy varies randomly from grain to grain. The skyrmion velocity is computed for different disorder parameters and ensembles. Similar behavior is seen for spin-torques due to in-plane currents and the spin Hall effect, where a pinning regime can be identified at low currents with a transition towards the disorder-free case at higher currents, similar to domain wall motion in disordered films. Moreover, a current-dependent skyrmion Hall effect and fluctuations in the core radius are found, which result from the interaction with the pinning potential.

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Joo-Von Kim, Myoung-Woo Yoo. 2017-01-29. Current-driven skyrmion dynamics in disordered films. https://doi.org/10.1063/1.4979316

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