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arXiv · 1904.06870

Current-driven nucleation and propagation of antiferromagnetic skyrmionium

S. A. Obadero·Y. Yamane·C. A. Akosa·G. Tatara
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Abstract

We present a theoretical study on nucleation and propagation of antiferromagnetic skyrmionium induced by spin current injection. A skyrmionium, also known as 2π skyrmion, is a vortex-like magnetic structure characterized by a topological charge, the so-called skyrmion number, being zero. We find that an antiferromagnetic skyrmionium can be generated via a local injection of spin current with toroidal distribution. A spatially uniform spin current is then demonstrated to induce a propagation of the skyrmionium. We derive an expression for the skyrmionium velocity based on a collective-coordinate model, which agrees well with our numerical results. Our findings suggest a novel way of nucleating an antiferromagnetic skyrmionium, as well as an analytical estimation of the current-driven skyrmionium velocity.

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S. A. Obadero, Y. Yamane, C. A. Akosa, G. Tatara. 2019-04-15. Current-driven nucleation and propagation of antiferromagnetic skyrmionium. https://doi.org/10.1103/physrevb.102.014458

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