Manupulation of gas atom spins by adsorption on ferromagnet surfaces

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K13864
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 13020:Semiconductors, optical properties of condensed matter and atomic physics-related
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Asakawa Kanta 東京農工大学, 工学(系)研究科(研究院), 助教 (50817046)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: スピン偏極 / 光誘起脱離 / 磁性体 / 原子物理学

Outline of Final Research Achievements

In this study, we aimed to elucidate the mechanism of the light-induced desorption of Rb from Fe3O4(001) surface by using a method which measures the spin state and motion state of desorbed Rb atoms. A Fe3O4 thin film deposited on the MgO(001) surface by electron beam evaporation and a magnetized by applying magnetic field was used. The results showed that under the conditions used in this study, photo-induced desorption did not occur below a certain coverage, and that the desorption was driven by a thermal mechanism. Furthermore, it was revealed that the desorbed Rb atoms were not spin-polarized. These suggest that light-induced desorption occurs only in the multilayer regime and that the desorbing atoms do not directly interact with the spin-polarized Fe3O4 surface.

Free Research Field

表面物理学

Academic Significance and Societal Importance of the Research Achievements

本研究では、フェリ磁性体Fe3O4表面から光誘起脱離したRb原子のスピン偏極度を測定し、脱離メカニズムの解明に役立てた。その結果、脱離のメカニズムは熱的であり、脱離はRbの吸着量がある一定の値以上の領域でのみ観測されることが分かった。また、脱離原子のスピン偏極度は検出感度以下であり、Fe3O4表面の伝導電子のスピン偏極度より有意に小さかった。これらの結果は、Rbの光誘起脱離が多層吸着領域でのみ起こることを示唆している。本研究で用いた手法は今後スピンが関わる様々な表面過程の解明に役立つことが期待される。