Establishment of study on pressure effects of spin nano-systems

2022 Fiscal Year Final Research Report

• Project/Area Number: 18K04875
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 28020:Nanostructural physics-related
• Research Institution: Kyushu University
• Principal Investigator: Mitsuda Akihiro 九州大学, 理学研究院, 准教授 (20334708)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Keywords: スピントロニクス / 圧力効果

Outline of Final Research Achievements

Recently, a variety of novel phenomena associated with spin degree of freedom in nanometer-size structures of magnetic materials have been discovered and examined extensively. This field, which is called spintronics, has attracted attention and extended novel application to such advanced devices as a sensor, a memory, and so on. This study is a trial to bring pressure effects to the spintronics field. Study of pressure effects on bulk materials has been a powerful tool and given us fruitful information. However, study of pressure effect on spintronics has been hardly carried out. In this study, we overcome difficulties of high-pressure experiments of spintronics materials and succeed in measuring giant magnetoresistance (GMR) effects in exchange-biased spin valve devices and spintronic phenomena accompanied by spin pumping induced by ferromagnetic resonance (FMR) under high pressure. Pressure effects enable us to discuss spintronic phenomena with preserving conditions except pressure.

Free Research Field

磁性物理学

Academic Significance and Societal Importance of the Research Achievements

圧力効果の研究はバルク結晶体の物性研究において強力な研究手段となっており、新しい高温超伝導体の発見など様々な研究に使われてきた。特に元素ドープなどの手法に比べると結晶のランダムネスの影響がなく、同一の試料を用いて圧力の変化による現象の変化を追いかけられる点は有利である。しかし、スピントロニクス現象に関する圧力効果の研究は15年ほど前に少し存在するのみで、殆ど行われてこなかった。本研究では、ナノ構造に圧力を加える際や圧力セル内に高周波信号を導入する際の困難を克服し、圧力実験の可能性を広げた。今後、現象の解明やデバイス開発の最適値を探る上で、圧力実験は強力な手法の1つとなりうると考える。