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arXiv · 1707.05267

Antiferromagnetic skyrmion crystals: generation, topological Hall and topological spin Hall effect

Börge Göbel·Alexander Mook·Jürgen Henk·Ingrid Mertig
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Abstract

Skyrmions are topologically nontrivial, magnetic quasi-particles, that are characterized by a topological charge. A regular array of skyrmions - a skyrmion crystal (SkX) - features the topological Hall effect (THE) of electrons, that, in turn, gives rise to the Hall effect of the skyrmions themselves. It is commonly believed that antiferromagnetic skyrmion crystals (AFM-SkXs) lack both effects. In this Rapid Communication, we present a generally applicable method to create stable AFM-SkXs by growing a two sublattice SkX onto a collinear antiferromagnet. As an example we show that both types of skyrmion crystals - conventional and antiferromagnetic - exist in honeycomb lattices. While AFM-SkXs with equivalent lattice sites do not show a THE, they exhibit a topological spin Hall effect. On top of this, AFM-SkXs on inequivalent sublattices exhibit a nonzero THE, which may be utilized in spintronics devices. Our theoretical findings call for experimental realization.

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Börge Göbel, Alexander Mook, Jürgen Henk, Ingrid Mertig. 2017-07-17. Antiferromagnetic skyrmion crystals: generation, topological Hall and topological spin Hall effect. https://doi.org/10.1103/physrevb.96.060406

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