2022 Fiscal Year Final Research Report

Design and property prediction of post-graphene thin-film materials based on first-principles electronic-state calculation

Research Project

PDF

Project/Area Number	20K05274
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 28030:Nanomaterials-related
Research Institution	Kyoto University of Advanced Science
Principal Investigator	Nakamura Koichi 京都先端科学大学, 工学部, 教授 (20314239)
Co-Investigator(Kenkyū-buntansha)	羽部哲朗京都先端科学大学, ナガモリアクチュエータ研究所, 助教 (60737435)
Project Period (FY)	2020-04-01 – 2023-03-31
Keywords	ポストグラフェン / 遷移金属ダイカルコゲナイド / 第一原理計算 / 時間依存密度汎関数理論 / 光学物性
Outline of Final Research Achievements	The electronic structures including their excited states in various post-graphene materials such as transition metal dichalcogenides have been clarified by precise electronic structure calculations, and the relationships between the electronic structures and the periods or groups of the constituent elements have been qualitatively and quantitatively analyzed. Time-dependent density functional theory was introduced to calculate the electronic excited states, and simulations were carried out for photoconductivity, dielectric function, I-V characteristics, piezoresistivity, piezooptical property, and thermoelectricity based on the electronic-state calculations. Theoretical indicators were provided for the fabrication policy of heterojunction structures and expected novel functions of post-graphene materials, and guidelines for the development of high-performance 2D materials with excellent electronic properties were presented.
Free Research Field	量子材料科学
Academic Significance and Societal Importance of the Research Achievements	ホーエンベルク・コーンの定理に基づく密度汎関数法は電子基底状態で成立する手法であり、価電子帯のエネルギーやバンドギャップが過小評価される等、電子励起状態に基づく材料特性の予測シミュレーションにはに対応できなかったが、材料系において時間依存密度汎関数法による電子状態計算を導入し、適正な電子励起状態のエネルギーバンドやコーン・シャム波動関数から材料物性を予測する手法の開発について先鞭をつけた。本研究で開発されたシミュレーション手法は、電子励起状態への遷移を伴う材料物性を利用した小型デバイス等を開発する際における材料選択に活用できる。