Improve the understanding of the mechanism of spin-orbit torque induced magnetization reversal and construct the material and device technologies based on it

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K13796
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 21060:Electron device and electronic equipment-related
• Research Institution: Tohoku University
• Principal Investigator: Zhang Chaoliang 東北大学, 学際科学フロンティア研究所, 助教 (80807678)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: スピントロニクス

Outline of Final Research Achievements

Magnetoresistive random-access memory has attracted significant attention these years as a promising alternative to the current volatile random-access memory technologies. Since it stores information as the magnetization directions of ferromagnetic thin films in magnetic tunnel junctions (MTJs), no energy is required to retain bit information. Meanwhile, the schemes which can reverse the magnetization direction with lower power consumption and faster speed become extremely important. In this work, we systematically study the magnetization reversal via spin-transfer torque (STT) and spin-orbit torque (SOT) in the ultra-fast regime 200 ps < tp < 1ns. We find that low-current fast switching can be achieved by modifying the combination of STT and SOT. Our findings are expected to provide clues for understanding the magnetization reversal mechanism with STT&SOT and eventually pave the way towards the nonvolatile spintronics device with high-speed and low-power-consumption performance.

Free Research Field

電子工学

Academic Significance and Societal Importance of the Research Achievements

本研究により、高性能なSOT-MTJ素子の材料設計、デバイス設計に関する系統的な理解が得られる。これらの知見を応用することで、製造が容易な構造で、高速動作、高信頼性、高い書き込み耐性を実現できるメモリ素子の実現が期待される。このため学術界に大きなインパクトを与える同時に、産業界へも高い貢献にもつながると考えられる。