Skyrmion dynamics in ultrathin films

Skyrmions are nanoscale spin structures that are stabilized by the Dzyaloshinskii-Moriya interaction. Because they possess a nontrivial topology, skyrmions are less susceptible to defects and edge roughness, which could be exploited for potential applications in information processing. Their existence in ultrathin films has been revealed in recent experiments and many studies are underway to probe their propagation dynamics.

Since 2013, the NOMADE group has conducted a number of theoretical and simulation studies of skyrmion dynamics in ultrathin film nanostructures. One highlight involves the identification of breathing modes in sub-micron discs, which result in an atypical microwave response that could be used to probe their existence experimentally.

Spatial profiles of the skyrmion breathing modes in magnetic nanostructures. After J.-V. Kim et al., Phys. Rev. B (2014).

More recent work has focused on oscillatory dynamics using spin-transfer torques, which relies partly on boundary edge confinement effects. The group has also explored the role of realistic disorder on current-driven skyrmion propagation, where features such as an extrinsic component to the skyrmion Hall motion have been brought to light.

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