Control of spin-orbit torque by quantum-well effect: a new way to the charge-spin current conversion

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14523
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 29010:Applied physical properties-related
• Research Institution: National Institutes for Quantum Science and Technology (2022-2023); Tohoku University (2021)
• Principal Investigator: DU Ye 国立研究開発法人量子科学技術研究開発機構, 高崎量子応用研究所 量子機能創製研究センター, 主任研究員 (70795319)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: スピン軌道トルク

Outline of Final Research Achievements

Aiming at the realization of efficient charge-spin current conversion and low-energy consumption in current-induced spin-orbit torque devices, we have studied the current-induced spin-orbit torques in (001)Cu/Co bilayer hetero-structure as a function of Cu layer thickness. As a result, the spin-orbit torque oscillates as a function of Cu thickness, where the oscillation period agrees with the interlayer exchange coupling theory which is interpreted with a quantum confinement model. Our results suggest that the current-induced spin-orbit torque in (001)Cu/Co can be controlled by coherent confinement of electrons in Cu.

Free Research Field

材料工学

Academic Significance and Societal Importance of the Research Achievements

本研究により、磁性金属/非磁性金属ヘテロ構造の量子閉じ込め効果を利用して電流誘起スピン軌道トルクを制御できることが明らかになった。本成果は、電流-スピン流変換に新しい自由度を提供するものであり、今後、本効果による磁化制御の高効率化を図ることでSOT素子の実用化に繋がることが期待できる。