Tuning of ferrimagnetism and perpendicular magnetic anisotropy in NiCo2O4 epitaxial films by the cation distribution

• DOI: 10.1103/physrevb.101.094412
• Publication Date: 2020-03-12T08:03:50Z
• Authors: Yufan Shen; Daisuke Kan; Zhenhong Tan; Yusuke Wakabayashi; Yuichi Shimakawa
• Keywords: Ferrimagnetism

Cation distribution in transition-metal oxides is closely tied to their physical properties. Here we employed resonant x-ray-diffraction technique and quantitatively evaluated the cation inverse spinel $\mathrm{NiC}{\mathrm{o}}_{2}{\mathrm{O}}_{4}$ films that were epitaxially grown by pulsed laser deposition. Our results reveal oxygen partial pressure during growth ${P}_{\mathrm{O}2}$ a key parameter determining films, with larger leading an increase Ni concentration occupying octahedral $({O}_{h})$ sites. We further show ${P}_{\mathrm{O}2}$-dependent ${O}_{h}$-site impacts magnetic properties of films: Films having close stoichiometric exhibit ferrimagnetism transition temperature higher than 400 K enhanced perpendicular anisotropy. On other hand, reductions leads deterioration ferrimagnetic such as magnetization, temperature, anisotropy energy. study demonstrates can be tuned through distribution, which would provide additional degree freedom designing spintronic devices based on including $\mathrm{NiC}{\mathrm{o}}_{2}{\mathrm{O}}_{4}$.