Mitigation of Magnus Force in Current-Induced Skyrmion Dynamics

Current-driven skyrmions drift from the intended direction of motion in a thin magnetic film due to the presence of the Magnus force and are annihilated upon reaching the film edge. This paper proposes two methods to engineer a 1-D potential well to confine the skyrmion motion in the center region of nanowires, thus preventing annihilation. By patterning the magnetic anisotropy of the film or by adding a layer of magnetic material at the edges, the barrier height and width of the potential well can be controlled. Magnetic skyrmions in such nanowires can then be guided to traverse only along the axis of the nanowire, even in the nanowires with steep bends. In addition, we also report a compression mechanism in which the skyrmion size and separation distance can be reduced by modifying the potential well, thus increasing the skyrmion packing density in a nanowire. The guided motion and high skyrmion density made possible by our proposed methods will allow the realization of high-density skyrmion-based memory.

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