Magnetism in ultra-thin metallic film deposited directly on a polar oxide

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K13359
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Thin film/Surface and interfacial physical properties
• Research Institution: The University of Tokyo
• Principal Investigator: Daichi Chiba 東京大学, 大学院工学系研究科(工学部), 准教授 (10505241)
• Co-Investigator(Renkei-kenkyūsha): TSUKAZAKI Atsushi 東北大学, 金属材料研究所, 教授 (50400396)
• Research Collaborator: SHIBATA Naoya 東京大学, 大学院工学系研究科, 准教授 (10376501)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 界面 / 極性酸化物 / 強磁性超薄膜 / 金属強磁性体

Outline of Final Research Achievements

A ferromagnetic-metal/oxide stack is one of the key structures that determines the spintronic device performance. However, the effect of the electronic polarity of the oxide on the magnetic properties of the adjacent ferromagnetic layer has not been understood. In this study, we show the magnetic and structural properties of Co ultra-thin films deposited directly on the Zn- and O-polar surfaces of ZnO substrates. The magnetic anisotropy and Curie temperature show dramatic differences for films on these surfaces. We confirmed that the Co/O-polar-surface hetero-interface is rather diffusive, whereas that of the Co/Zn-polar-surface is atomically flat. These results suggest that the surface polarity plays a important role in determining the properties of the film. This novel FM-metal/polar-oxide system is expected to add new functionality to spintronic devices.

Free Research Field

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