Deterministic Generation and Guided Motion of Magnetic Skyrmions by Focused He$^+$-Ion Irradiation

TL;DR

This paper demonstrates a method to precisely control the creation and guided movement of magnetic skyrmions using focused He$^+$-ion irradiation to pattern anisotropy landscapes, enabling deterministic skyrmion positioning.

Contribution

The study introduces a novel nanopatterning technique with He$^+$-ion beams to achieve deterministic nucleation and guided motion of skyrmions, surpassing previous random nucleation methods.

Findings

Nanopatterning creates well-defined skyrmion nucleation sites.

Controlled skyrmion motion achieved with nanometer-scale precision.

Enables deterministic skyrmion manipulation for future applications.

Abstract

Magnetic skyrmions are quasiparticles with non-trivial topology, envisioned to play a key role in next-generation data technology while simultaneously attracting fundamental research interest due to their emerging topological charge. In chiral magnetic multilayers, current-generated spin-orbit torques or ultrafast laser excitation can be used to nucleate isolated skyrmions on a picosecond timescale. Both methods, however, produce randomly arranged skyrmions, which inherently limits the precision on the location at which the skyrmions are nucleated. Here, we show that nanopatterning of the anisotropy landscape with a He$^+$-ion beam creates well-defined skyrmion nucleation sites, thereby transforming the skyrmion localization into a deterministic process. This approach allows to realize control of individual skyrmion nucleation as well as guided skyrmion motion with nanometer-scale precision, which is pivotal for both future fundamental studies of skyrmion dynamics and applications.