High-temperature superconductivity in FeSe films studied by angle-resolved photoemission spectroscopy

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H04847
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Condensed matter physics II
• Research Institution: Tohoku University
• Principal Investigator: Nakayama Kosuke 東北大学, 理学研究科, 助教 (40583547)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 角度分解光電子分光 / 高温超伝導 / 鉄系超伝導体 / 薄膜

Outline of Final Research Achievements

We have investigated the superconducting mechanism in ultrathin iron-based superconductors and also searched for high-temperature superconductivity. By improving an angle-resolved photoemission spectrometer and a molecular-beam epitaxy system, we have grown ultrathin films of iron-based superconductors with various compositions, carrier concentrations, and thicknesses. By determing their superconducting temperatures and electronic structures, we have succeeded in achieving high-temperature superconductivity, determining the phase diagram, and uncovering exotic properties. Our detailed ARPES studies provide important insights into the mechanism of high-temperature superconductivity.

Free Research Field

光電子固体物性

Academic Significance and Societal Importance of the Research Achievements

本研究では、原子数個程度の厚さの薄膜試料において高温超伝導を実現・制御する手法を確立した。基礎と応用を跨ぐ広範な分野において、最も重要な研究テーマの１つである高温超伝導は、これまでバルク試料の研究が大部分を占めていた。本研究で確立した手法を用いることで、既存のバルク高温超伝導物質では実現が困難な応用や、原子層薄膜に特有の新たな高温超伝導メカニズムに関する研究の進展が期待される。