Many-body interactions on two-dimensional electronic states formed in transition-metal oxides

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K14325
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics I
• Research Institution: High Energy Accelerator Research Organization
• Principal Investigator: Yukawa Ryu 大学共同利用機関法人高エネルギー加速器研究機構, 物質構造科学研究所, 特任助教 (40759479)
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: 角度分解光電子分光 / 酸化物 / バンド構造 / 電子状態 / 多体間相互作用 / 表面

Outline of Final Research Achievements

In this study, stable electron doping method on transition-metal oxide surfaces has been established, and many-body interactions in two-dimensional electronic states (2DES) formed in a transition-metal oxide have been elucidated both by angle-resolved photoemission spectroscopy and by electronic conductivity. The main results are as follows.
(1) We have developed an alkali-metal deposition system which enables a precise control of the electron doping on transition metal oxide surfaces. (2) The origin of many-body interactions in 2DES formed at an anatase TiO2 surface has been clarified. (3) We found the difference in electron-phonon interactions between at the anatase TiO2 surface and in the bulk.

Free Research Field

低次元電子物性

Academic Significance and Societal Importance of the Research Achievements

遷移金属酸化物においては電子輸送特性に対する多体間相互作用の寄与が大きいため、酸化物物質設計・物性制御においてキャリア密度に応じた詳細な多体間相互作用の解明が必要不可欠である。特に電子デバイスの微細化に伴う低次元系の研究において、表面・極薄膜での電子的振る舞いを理解する事が必要不可欠である。そのため、低次元系での電子の多体間相互作用を明らかにした本成果は高い重要性と発展性を持つものと考えられる。