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.
@article{arxiv.2206.00791,
title = {Enhanced thermally-activated skyrmion diffusion with tunable effective gyrotropic force},
author = {Takaaki Dohi and Markus Weißenhofer and Nico Kerber and Fabian Kammerbauer and Yuqing Ge and Klaus Raab and Jakub Zàzvorka and Maria-Andromachi Syskaki and Aga Shahee and Moritz Ruhwedel and Tobias Böttcher and Philipp Pirro and Gerhard Jakob and Ulrich Nowak and Mathias Kläui},
journal= {arXiv preprint arXiv:2206.00791},
year = {2023}
}