Demonstration of Controlled Skyrmion Injection Across a Thickness Step

Littlehales, Matthew T.; Moody, Samuel H.; Turnbull, Luke A.; Huddart, Benjamin M.; Brereton, Ben A.; Balakrishnan, Geetha; Fan, Raymond; Steadman, Paul; Hatton, Peter D.; Wilson, Murray N.

Abstract

Spintronic devices incorporating magnetic skyrmions have attracted significant interest recently. Such devices traditionally focus on controlling magnetic textures in 2D thin films. However, enhanced performance of spintronic properties through the exploitation of higher dimensionalities motivates the investigation of variable-thickness skyrmion devices. We report the demonstration of a skyrmion injection mechanism that utilizes charge currents to drive skyrmions across a thickness step and, consequently, a metastability barrier. Our measurements show that under certain temperature and field conditions skyrmions can be reversibly injected from a thin region of an FeGe lamella, where they exist as an equilibrium state, into a thicker region, where they can only persist as a metastable state. This injection is achieved with a current density of 3 × 108 A m–2, nearly 3 orders of magnitude lower than required to move magnetic domain walls. This highlights the possibility to use such an element as a skyrmion source/drain within future spintronic devices.

Citation

Littlehales, M. T., Moody, S. H., Turnbull, L. A., Huddart, B. M., Brereton, B. A., Balakrishnan, G., Fan, R., Steadman, P., Hatton, P. D., & Wilson, M. N. (2024). Demonstration of Controlled Skyrmion Injection Across a Thickness Step. Nano Letters, 24(22), 6813-6820. https://doi.org/10.1021/acs.nanolett.4c01605

• Journal Article Type: Article
• Acceptance Date: May 17, 2024
• Online Publication Date: May 23, 2024
• Publication Date: Jun 5, 2024
• Deposit Date: May 31, 2024
• Publicly Available Date: May 31, 2024
• Journal: Nano Letters
• Print ISSN: 1530-6984
• Electronic ISSN: 1530-6992
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 24
• Issue: 22
• Pages: 6813-6820
• DOI: https://doi.org/10.1021/acs.nanolett.4c01605
• Keywords: 3D magnetic nanostructures, small-angle X-ray scattering, magnetic skyrmions
• Public URL: https://durham-repository.worktribe.com/output/2468628