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arXiv · 2206.00791

Enhanced thermally-activated skyrmion diffusion with tunable effective gyrotropic force

Takaaki Dohi·Markus Weißenhofer·Nico Kerber·Fabian Kammerbauer·Yuqing Ge·Klaus Raab·Jakub Zàzvorka·Maria-Andromachi Syskaki·Aga Shahee·Moritz Ruhwedel·Tobias Böttcher·Philipp Pirro·Gerhard Jakob·Ulrich Nowak·Mathias Kläui
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Abstract

Magnetic skyrmions, topologically-stabilized spin textures that emerge in magnetic systems, have garnered considerable interest due to a variety of electromagnetic responses that are governed by the topology. The topology that creates a microscopic gyrotropic force also causes detrimental effects, such as the skyrmion Hall effect, which is a well-studied phenomenon highlighting the influence of topology on the deterministic dynamics and drift motion. Furthermore, the gyrotropic force is anticipated to have a substantial impact on stochastic diffusive motion; however, the predicted repercussions have yet to be demonstrated, even qualitatively. Here we demonstrate enhanced thermally-activated diffusive motion of skyrmions in a specifically designed synthetic antiferromagnet. Suppressing the effective gyrotropic force by tuning the angular momentum compensation leads to a more than 10 times enhanced diffusion coefficient compared to that of ferromagnetic skyrmions. Consequently, our findings not only demonstrate the gyro-force dependence of the diffusion coefficient but also enable ultimately energy-efficient unconventional stochastic computing.

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Takaaki Dohi, Markus Weißenhofer, Nico Kerber, Fabian Kammerbauer, Yuqing Ge, Klaus Raab, Jakub Zàzvorka, Maria-Andromachi Syskaki, Aga Shahee, Moritz Ruhwedel, Tobias Böttcher, Philipp Pirro, Gerhard Jakob, Ulrich Nowak, Mathias Kläui. 2023-09-11. Enhanced thermally-activated skyrmion diffusion with tunable effective gyrotropic force. https://doi.org/10.1038/s41467-023-40720-0

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