Development of a double magnetic resonance measurement technique for direct observation of spin currents in organic semiconductors

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K22172
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 32:Physical chemistry, functional solid state chemistry, and related fields
• Research Institution: Osaka City University
• Principal Investigator: Kanemoto Katsuichi 大阪市立大学, 大学院理学研究科, 准教授 (40336756)
• Project Period (FY): 2019-06-28 – 2022-03-31
• Keywords: スピン流 / 磁気共鳴 / 二重共鳴

Outline of Final Research Achievements

We have constructed a pump-probe type dual magnetic resonance spin current observation system in which a ferromagnetic electrode is spin pumped by ferromagnetic resonance in the X band to generate a spin current, and the accumulated state of spin polarization after propagation can be excited directly from an antenna at a resonance frequency different from the X band. We confirmed that microwave excitation from the antenna can actually be performed. We also confirmed that the double resonance experiment is possible without interference between the X band microwaves and the microwaves from the antenna in the device consisting of ferromagnetic electrode 1/paramagnetic layer/ferromagnetic electrode 2.

Free Research Field

スピン物性物理

Academic Significance and Societal Importance of the Research Achievements

近年スピン分極状態の空間伝播を意味する“スピン流”に関する研究が注目されているが、その伝播を直接観測することは難しかった。この研究では、そのスピン流を発生させるマイクロ波照射システムと、スピン流の到達を検出できるマイクロ波吸収観測システムを組み合わせ、スピン流の伝達を評価できる計測系の構築に取り組み、実際に両方のマイクロ波が干渉せず、実験が行えることを確認できた。今後スピン流物性の検証に活用できる。