Characterization and control of spin dynamics by spin-resonance scanning tunneling microscopy

2022 Fiscal Year Final Research Report

• Project/Area Number: 19H00859
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 29:Applied condensed matter physics and related fields
• Research Institution: The University of Tokyo
• Principal Investigator: Hasegawa Yukio 東京大学, 物性研究所, 教授 (80252493)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 走査トンネル顕微鏡 / スピン偏極走査トンネル顕微鏡 / 強磁性共鳴

Outline of Final Research Achievements

In order to realize ferromagnetic resonance using a scanning tunneling microscope, we have introduced microwaves into existing equipment and have succeeded in detecting high-frequency waves at the probe-sample gap and in maintaining constant intensity during the sweep of the frequency by feedback control. We have also carefully examined the sample conditions required for ferromagnetic resonance based on numerical simulations, and found that systems with low magnetic anisotropy are suitable for our experimental conditions. As a system with low magnetic anisotropy, we focused on van der Waals magnets and succeeded in fabricating monolayer films of van der Waals magnets. We have also started development of spin-polarized potentiometry to detect resonance by spin current detection instead of spin polarization by the resonance, and confirmed that it works under ultrahigh vacuum and at low temperatures.

Free Research Field

表面科学・ナノサイエンス

Academic Significance and Societal Importance of the Research Achievements

個々の原子やナノ磁性体のスピン・磁化情報のダイナミクスを検出することは、これまでにない技術であり、その観測は学術的意義が極めて高いと言える。走査トンネル顕微鏡による原子構造・電子状態、さらにはスピン偏極走査トンネル顕微鏡による静的な磁化・スピン情報と組み合わせることによって、強力な磁気分析ツールとなり得る可能性を秘めている。