Regensburg 2022 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
KFM: Fachverband Kristalline Festkörper und deren Mikrostruktur
KFM 12: Skyrmions 1 (joint session MA/KFM)
KFM 12.9: Talk
Tuesday, September 6, 2022, 11:45–12:00, H37
Skyrmion Pinning Energetics in Thin Film Systems — Raphael Gruber1, Jakub Zázvorka1, •Maarten A. Brems1, Davi R. Rodrigues1, Takaaki Dohi1, Nico Kerber1, Boris Seng1, Mehran Vafaee-Khanjani1, Karin Everschor-Sitte2, Peter Virnau1, and Mathias Kläui1 — 1Institute of Physics, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany — 2CENIDE, University of Duisburg-Essen, 47057 Duisburg, Germany
Magnetic skyrmions in thin films have been shown to exhibit thermal diffusion, making them a promising system for applications in probabilistic computing [1] as well as Brownian computing [2]. In such applications, pinning effects are of crucial importance as the pinning strength is often comparable to thermal excitations and thus impacts the operation of skyrmion-based devices. Using thermal skyrmion dynamics, we characterize the pinning in a sample and ascertain the spatially resolved energy landscape [3]. To understand the mechanism of pinning, we image the skyrmion pinning details and find a strong size-dependence. We observe that the skyrmion is pinned at its boundary (domain wall) and not as previously considered at its core. As a consequence, we find that the size-dependence follows from different favorable overlaps of the skyrmion boundary with the pinning regions, which is supported by micromagnetic simulations. This allows us to switch pinning sites on and off by small tuning of external fields. [1] J. Zázvorka et al., Nat. Nanotechnol. 14, 658 (2019). [2] M. A. Brems et al., Appl. Phys. Lett. 119, 132405 (2021). [3] R. Gruber et al., under review (2021).