Development of high-speed low-power magnetization reversal method using two SOTs

2023 Fiscal Year Final Research Report

• Project/Area Number: 20H02607
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 29010:Applied physical properties-related
• Research Institution: Kansai University
• Principal Investigator: Honda Syuta 関西大学, システム理工学部, 准教授 (00402553)
• Co-Investigator(Kenkyū-buntansha): 安藤 裕一郎 京都大学, 工学研究科, 准教授 (50618361)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: スピン注入磁化反転 / マイクロマグネティクス / スピン軌道トルク

Outline of Final Research Achievements

The objective was to achieve high-speed and low-power operation through the use of the Spin-Orbit Torque (SOT) method. In particular, the focus was on in-plane magnetization reversal. During the reversal process, spins were initially injected perpendicular to the magnetization direction, which resulted in a tilting of the magnetization. Subsequently, spins were injected in the direction of reversal. Consequently, in comparison to the conventional, straightforward SOT magnetization reversal approach, the experimental data revealed a 70% reduction in power consumption, while the simulation results indicated a 95% reduction. New structures for fast magnetization switching were proposed by the simulation of magnetization switching and numerical calculation of spin currents.

Free Research Field

物性理論

Academic Significance and Societal Importance of the Research Achievements

補助書込SOT法による高速・低消費電力磁化反転では，情報書換時の消費電力の多さが欠点だった磁気メモリが，情報書換時の消費電力の少なさが利点，と言えるほどに電力消費を改善できることが示された。さらに，回路設計によるスピン注入最適化の効果が高いことを示しており，空間的，時間的スピン注入の最適化で，これまでの磁化反転の常識を大きく覆すことが可能であることが期待される。このように研究成果は学術的意義が高い。また，磁化反転の応用デバイスMRAMが車載メモリとしての実用化されるなど需要が高まりつつある昨今，超省エネルギー磁化反転を一日でも早く実現する必要があり，本成果の社会的意義も高い。