Development of evaluation method for thin film magnetism by spin Hall magnetoresistance

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K20497
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0402:Nano/micro science, applied condensed matter physics, applied physics and engineering, and related fields
• Research Institution: Tohoku University
• Principal Investigator: Masamichi Negishi 東北大学, 金属材料研究所, 特任助教 (70911147)
• Project Period (FY): 2021-08-30 – 2023-03-31
• Keywords: 磁性体薄膜 / 反強磁性 / 常磁性 / イルメナイト型構造 / チタン酸化物 / イリジウム酸化物

Outline of Final Research Achievements

In this project, thin films of ilmenite-type non-magnetic MgTiO3 and antiferromagnetic ATiO3 (A = Mn, Fe, Co, Ni) were synthesized. For all materials, crystalline thin films whose crystalline orientation is aligned along the out-of-plane direction were obtained. For MgTiO3 and MnTiO3, conditions of deposition of thin film were optimized and twin-suppressed single-crystalline thin films of the ilmenite phases were formed. In addition, Mg-Ir-O films were deposited with the aim to form another ilmenite-type magnet. In that process, a method to control Mg/Ir composition ratio in thin films was developed.

Free Research Field

結晶性薄膜

Academic Significance and Societal Importance of the Research Achievements

薄膜において常磁性や反強磁性などの磁気状態を判別することは、学術・応用両面において重要な課題である。しかし、これらの磁気状態では磁場に対する応答が小さいため、微小体積の薄膜において、これらの磁気状態を区別することが難しい。本研究では、薄膜で発現する常磁性や反強磁性を電気伝導測定によって判別する方法を開発する際に参照物質となる、同型の結晶構造をもった非磁性体・反強磁性体薄膜試料群を合成した。