Controllingmagnetism in 3d transition metal oxides through spin-orbit interactions

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H04813
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Thin film/Surface and interfacial physical properties
• Research Institution: Kyoto University
• Principal Investigator: Kan Daisuke 京都大学, 化学研究所, 准教授 (40378881)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 遷移金属酸化物 / スピン軌道相互作用 / 磁気異方性 / ヘテロ構造 / 遷移金属-酸素結合 / エピタキシャル薄膜

Outline of Final Research Achievements

In this research project, we explored functional properties originating from spin-orbit interactions in oxide heterostructures. We find that magnetic anisotropy in transition metal oxides can be controlled by heterostructuring them and modulating their metal-oxygen bonds. Imposing compressive strain through the structural mismatch is found to be useful to stabilize the perpendicular magnetic anisotropy in oxides. In addition, we successfully fabricated the inverse spinel oxide NiCo2O4 that has both half-metallic band structure and sufficient perpendicular magnetic anisotropy, although these two properties rarely coexist. We also clarified the physical origin of anomalies in transverse resistivity, which resemble what has been claimed to be the topological Hall effect in oxide heterostructures,

Free Research Field

薄膜材料科学

Academic Significance and Societal Importance of the Research Achievements

遷移金属酸化物は、古くから磁性材料として、研究・開発されてきた。今回スピン軌道相互作用に関連した磁気特性である磁気異方性の制御などについて新たな知見が得られた。今後の材料開発の新たな指針となると期待できる。例えばハーフメタルなど、これまで磁気異方性の制御が困難と考えられていた材料に垂直磁気異方性を付与することで新機能創出につながる。またスピン軌道相互作用に着目することで、酸化物ヘテロ構造におけるトポロジカルホール効果など新奇現象の発見も期待できる。