Magnetic skyrmions 1 are magnetic quasi-particles with interesting properties for possible future applications in efficient low-power neuromorphic computing concepts. Thermally excited skyrmions in confined geometries, as necessary for device applications, have been shown to arrange based on commensurability effects 2. Here, we investigate the enhanced dynamics and altered equilibrium state of a system in which the intrinsic skyrmion-skyrmion and skyrmion-boundary interaction compete with spin-orbit torques (SOTs) due applied currents 3. In particular, we employ particle-based simulations to study four skyrmions in a triangular confinement, while injecting spin-polarized currents between two corners of the structure 4. To analyze the observed positions of the skyrmion ensemble, we coarse-grain the skyrmion states in the system. In the context of neuromorphic computing, such coarse-graining may be key to identify the most suitable positions for potential readouts as well as to understand the collective skyrmion dynamics in systems with competing interactions at different scales.
1 K. Everschor-Sitte et al., Journal of Applied Physics 124, 240901 (2018)
2 C. Song et al., Adv. Funct. Mater. 31, 2010739 (2021)
3 K. Raab et al., arxiv:2204.14720 (2022)
4 T. Winkler et al., in preparation (2022)