Non-uniform Gd distribution and magnetization profiles within GdCoFe alloy thin films

Inyang, O.; Swindells, C.; Rianto, D.; Bouchenoire, L.; Morris, R. J. H.; Merkulov, A.; Caruana, A.; Kinane, C.; Hase, T. P. A.; Atkinson, D.

Abstract

Rare earth (RE):transition metal (TM) ferrimagnetic alloys continue to attract significant attention for spintronics. This work focuses on the elemental distribution of RE and TM elements throughout the thickness of nominally uniform films and the resulting spatial variations of the magnetization within these layers. Samples of CoFe alloyed with Gd were studied using secondary ion mass spectroscopy, polarized neutron reflectometry, and x-ray resonant magnetic reflectivity. The samples were grown by magnetron co-sputtering to control the RE:TM alloy ratio of the ferrimagnetic layer, which was combined with W and Pt layers as either under or over-layers to create sample structures such as
⁠, where x = 0, 8, and 23 at. %. Results show that uniformly deposited thin-films have a significant variation in the distribution of the TM and RE through the film thickness, and this leads to a spatial distribution in the net magnetization profile and a non-uniform Gd magnetization profile within the layer. These findings have implications for the application RE:TM alloys in spintronics as they may impact the perpendicular magnetic anisotropy, the ferrimagnetic compensation temperature, and interfacial spin transport.

Citation

Inyang, O., Swindells, C., Rianto, D., Bouchenoire, L., Morris, R. J. H., Merkulov, A., …Atkinson, D. (2023). Non-uniform Gd distribution and magnetization profiles within GdCoFe alloy thin films. Applied Physics Letters, 123(12), Article 122403. https://doi.org/10.1063/5.0165423

• Journal Article Type: Article
• Acceptance Date: Sep 4, 2023
• Online Publication Date: Sep 19, 2023
• Publication Date: Sep 18, 2023
• Deposit Date: Dec 7, 2023
• Publicly Available Date: Dec 7, 2023
• Journal: Applied Physics Letters
• Print ISSN: 0003-6951
• Electronic ISSN: 1077-3118
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 123
• Issue: 12
• Article Number: 122403
• DOI: https://doi.org/10.1063/5.0165423
• Keywords: Physics and Astronomy (miscellaneous)
• Public URL: https://durham-repository.worktribe.com/output/1984370