Spontaneous creation and annihilation dynamics and strain-limited stability of magnetic skyrmions.

Autor: Rendell-Bhatti F; SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK. f.rendell.1@research.gla.ac.uk., Lamb RJ; SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK., van der Jagt JW; Department of Applied Physics, Eindhoven University of Technology, 5612 AZ, Eindhoven, The Netherlands., Paterson GW; SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK., Swagten HJM; Department of Applied Physics, Eindhoven University of Technology, 5612 AZ, Eindhoven, The Netherlands., McGrouther D; SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2020 Jul 15; Vol. 11 (1), pp. 3536. Date of Electronic Publication: 2020 Jul 15.
DOI: 10.1038/s41467-020-17338-7
Abstrakt: Magnetic skyrmions are topological magnetic spin structures exhibiting particle-like behaviour. They are of strong interest from a fundamental viewpoint and for application, where they have potential to act as information carriers in future low-power computing technologies. Importantly, skyrmions have high physical stability because of topological protection. However, they have potential to deform according to their local energy environment. Here we demonstrate that, in regions of high exchange energy density, skyrmions may exhibit such extreme deformation that spontaneous merging with nearest neighbours or spawning new skyrmions is favoured to attain a lower energy state. Using transmission electron microscopy and a high-speed imaging detector, we observe dynamics involving distinct configurational states, in which transitions are accompanied by spontaneous creation or annihilation of skyrmions. These observations raise important questions regarding the limits of skyrmion stability and topological charge conservation, while also suggesting a means of control of skyrmion creation and annihilation.
Databáze: MEDLINE