Ferromagnetism in polycrystalline two-dimensional transition-metal chalcogenides and applications

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14193
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 21050:Electric and electronic materials-related
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Muneta Iriya 東京工業大学, 工学院, 助教 (90750018)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: スピントロニクス / 層状半導体 / ファンデアワールス強磁性体

Outline of Final Research Achievements

(1) MoS2 magnetometry was investigated. Magnetization was successfully measured on the samples grown at 300-500 degree. The sample grown above 500 is under consideration.
(2) Magnetoresistance of polycrystal MoS2 was observed, and magnetic field dependence of it was largely changed according to current intensity. I demonstrated ferromagnetism modulation by ultra-low current in the first time in the world.
(3) Layer-number-dependence of ferromagnetism in polycrystal MoS2 is being measured. It was confirmed that saturated magnetization is constant above three layers, but it decreased under 3 layers. This result is to be published after preparing auxiliary data.

Free Research Field

スピントロニクス

Academic Significance and Societal Importance of the Research Achievements

不揮発性磁気メモリの超微細化、および、三次元化の実現には、表面が原子レベルで平坦なファンデアワールス強磁性体が重要である。私が推進するファンデアワールス層状物質の二硫化モリブデンのエッジ強磁性の研究はその一端を担い、産業を振興することに繋がる。また、4d軌道を起源に持つ強磁性体は珍しく、加えて、エッジ構造のトポロジカル欠陥に起源するものと予想されている。非磁性であった物質を強磁性にする基礎研究は、物質科学の進展に大きく寄与する。