Brownian reservoir computing realized using geometrically confined skyrmions

TL;DR

This paper demonstrates a new experimental approach to skyrmion reservoir computing using thermally activated skyrmion motion in confined geometries, enabling low-power, scalable Boolean logic operations.

Contribution

It introduces the first experimental realization of skyrmion reservoir computing based on thermally diffusive skyrmion motion in confined geometries.

Findings

Single skyrmion in confinement can perform XOR and other logic gates

Reservoir computing with skyrmions operates at ultra-low power levels

The approach is scalable by linking multiple geometries or skyrmions

Abstract

Reservoir computing (RC) has been considered as one of the key computational principles beyond von-Neumann computing. Magnetic skyrmions, topological particle-like spin textures in magnetic films are particularly promising for implementing RC, since they respond strongly nonlinear to external stimuli and feature inherent multiscale dynamics. However, despite several theoretical proposals that exist for skyrmion reservoir computing, experimental realizations have been elusive until now. Here, we propose and experimentally demonstrate a conceptually new approach to skyrmion RC that leverages the thermally activated diffusive motion of skyrmions. By confining the electrically gated and thermal skyrmion motion, we find that already a single skyrmion in a confined geometry suffices to realize non-linearly separable functions, which we demonstrate for the XOR gate along with all other Boolean logic gate operations. Besides this universality, the reservoir computing concept ensures low training costs and ultra-low power operation with current densities orders of magnitude smaller than those used in existing spintronic reservoir computing demonstrations. Our proposed concept can be readily extended by linking multiple confined geometries and/or by including more skyrmions in the reservoir, suggesting high potential for scalable and low-energy reservoir computing.