Highly geometrically confined magnetic skyrmions

June 2017

by Chiming Jin, Zi-An Li, András Kovács, Jan Caron, Fengshan Zheng, Filipp N. Rybakov, Nikolai S. Kiselev, Haifeng Du, Stefan Blügel, Mingliang Tian, Yuheng Zhang, Michael Farle, and Rafal E Dunin-Borkowski

The ability to controllably manipulate magnetic skyrmions, small magnetic whirls with particle-like properties, in nanostructured elements is a prerequisite for incorporating them into spintronic devices.

Here, state-of-the-art electron holographic imaging is used to directly visualise the morphology and nucleation of magnetic skyrmions in a wedge-shaped FeGe nanostripe that has a width in the range of 45–150 nm.

It is found that geometrically-confined skyrmions are able to adopt a wide range of sizes and ellipticities in a nanostripe that are absent in both thin films and bulk materials and can be created from a helical magnetic state with a distorted edge twist in a simple and efficient manner.

A theoretical analysis based on a three-dimensional general model of isotropic chiral magnets is performed to confirm the experimental results. The flexibility and ease of formation of geometrically confined magnetic skyrmions may help to optimise the design of skyrmion-based memory devices.

Further reading:

Chiming Jin, Zi-An Li, András Kovács, Jan Caron, Fengshan Zheng, Filipp N. Rybakov, Nikolai S. Kiselev, Haifeng Du, Stefan Blügel, Mingliang Tian, Yuheng Zhang, Michael Farle, and Rafal E Dunin-Borkowski:
Control of morphology and formation of highly geometrically confined magnetic skyrmions,
Nature Communications 8 (2017) 15569.