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arXiv · 2407.02983

Current-induced motion of nanoscale magnetic torons over the wide range of the Hall angle

Kotaro Shimizu·Shun Okumura·Yasuyuki Kato·Yukitoshi Motome
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Abstract

Current-driven dynamics of spin textures plays a pivotal role in potential applications for electronic devices. While two-dimensional magnetic skyrmions with topologically nontrivial spin textures have garnered significant interest, their practical use is hindered by the skyrmion Hall effect $\unicode{x2014}$ a transverse motion to the current direction that occurs as a counteraction to the topological Hall effect of electrons by an emergent magnetic field arising from the Berry phase effect. Here, we explore current-driven dynamics of three-dimensional topological spin textures known as magnetic torons, composed of layered skyrmions with two singularities called Bloch points at their ends. Through extensive numerical simulations, we show that the torons also exhibit a Hall motion, but surprisingly over a wide range spanning from the zero Hall effect, a purely longitudinal motion, to the perfect Hall effect, a purely transverse motion accompanied by no longitudinal motion. Such flexible and controllable behaviors stem from anisotropic potential barriers on the discrete lattice, which can be particularly relevant for nanoscale torons recently discovered. Our results not only provide an experimental method to probe topology of three-dimensional magnetic textures but also pave the way for future developments in topological spintronics beyond the realm of skyrmions.

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Kotaro Shimizu, Shun Okumura, Yasuyuki Kato, Yukitoshi Motome. 2024-07-03. Current-induced motion of nanoscale magnetic torons over the wide range of the Hall angle. https://doi.org/10.1038/s42005-025-01970-0

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