TRR 360 Seminar:

Topological Spin-Orbitronics and Orbitronics for GreenIT

Mathias Kläui

Prof. Dr. Mathias Kläui

Institute of Physics, University of Mainz

Centre for Quantum Spintronics, Norwegian University of Science and Technology, Trondheim, Norway

Novel spintronic devices can play a role in the quest for GreenIT if they are stable and can transport and manipulate spin with low power. Devices have been proposed, where switching by energy-efficient approaches is used to manipulate topological spin structures [1].

We combine ultimate stability of topological states due to chiral interactions [1] with ultra-efficient manipulation using novel spin torques [2]. In particular orbital torques increase the switching efficiency by more than a factor 10. Recently we have demonstrated that using correlated orbital magnets, a factor 70 stronger interaction with orbital currents is found boding well for ultra-efficient manipulation [3].

We use skyrmion dynamics for non-conventional stochastic computing applications, where we developed skyrmion reshuffler devices based on skyrmion diffusion, which also reveals the origin of skyrmion pinning. Such diffusion can furthermore be used for Token-based Brownian Computing and Reservoir Computing [4].

References:

1. K. Everschor-Sitte et al., J. Appl. Phys. 124, 240901 (2018)

2. S. Fukami et al., Nature Phys. (2025) ; https://doi.org/10.1038/s41567-025-03143-w

3. C. Schmitt et al., Science 393, 76 (2026)

4. G. Beneke et al., Nature Commun. 15, 8103 (2024)