Magnetic domain wall pinning in cobalt ferrite microstructures

• Main Authors: Aballe, L. (Author), de la Figuera, J. (Author), Foerster, M. (Author), Mandziak, A. (Author), Martín-García, L. (Author), Munuera, C. (Author), Prieto, J.E (Author), Prieto, P. (Author), Quesada, A. (Author), Ruiz-Gómez, S. (Author)
• Format: Article
• Language: English
• Published: Elsevier B.V. 2022
• Subjects: Atomic-force-microscopy; Chemical analysis; Cobalt; Cobalt ferrites; Correlative microscopies; Correlative microscopy; Crystal atomic structure; Defects; Dichroism; Domain wall pinning; Domain walls; Domain-wall pinning; Electrons; Ferrite; Films; Low energy electron microscopy; Magnetic domain walls; Magnetic domains; Micrometric crystals; Nanomagnetics; Nonstoichiometric; Photoemission microscopy; X-ray magnetic circular dichroism
• Online Access: View Fulltext in Publisher
• ISBN: 01694332 (ISSN)
• DOI: 10.1016/j.apsusc.2022.154045

A detailed correlative structural, magnetic and chemical analysis of (non-stoichiometric) cobalt ferrite micrometric crystals was performed by x-ray magnetic circular dichroism combined with photoemission microscopy, low-energy electron microscopy and atomic force microscopy. The magnetization vector inside the islands was resolved at the nanoscale, as obtained from magnetic images taken at different x-ray incidence angles. The location of the magnetic domain walls was correlated with the presence of different types of defects as revealed by the different microscopies. This, together with the results of micromagnetic simulations, suggests that the main source of pinning in these microcrystals are linear structural defects induced in the spinel structure by the substrate steps underneath the islands. Our result is of relevance for understanding the different magnetic properties of thin films and nanostructures as compared with the corresponding bulk materials. © 2022 The Authors