Reduced magnetocrystalline anisotropy of CoFe2O4 thin films studied by angle-dependent x-ray magnetic circular dichroism

Autor: Yosuke Nonaka, Yuki K. Wakabayashi, Goro Shibata, Shoya Sakamoto, Keisuke Ikeda, Zhendong Chi, Yuxuan Wan, Masahiro Suzuki, Tsuneharu Koide, Masaaki Tanaka, Ryosho Nakane, Atsushi Fujimori
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: AIP Advances, Vol 11, Iss 8, Pp 085317-085317-5 (2021)
Druh dokumentu: article
ISSN: 2158-3226
DOI: 10.1063/5.0057576
Popis: Spinel-type CoFe2O4 is a ferrimagnetic insulator with the Néel temperature exceeding 790 K, and it shows strong cubic magnetocrystalline anisotropy (MCA) in bulk materials. However, when a CoFe2O4 film is grown on other materials, its magnetic properties are degraded so that so-called magnetically dead layers are expected to be formed in the interfacial region. We investigate how the magnetic anisotropy of CoFe2O4 is modified at the interface of CoFe2O4/Al2O3 bilayers grown on Si(111) using x-ray magnetic circular dichroism. We find that the thinner CoFe2O4 films have significantly smaller MCA values than bulk materials. The reduction in MCA is explained by the reduced number of Co2+ ions at the Oh site, as reported by a previous study [Wakabayashi et al., Phys. Rev. B 96, 104410 (2017)].
Databáze: Directory of Open Access Journals