Understanding glasses based on the energy landscape

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H04853
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Biological physics/Chemical physics/Soft matter physics
• Research Institution: The University of Tokyo
• Principal Investigator: Ikeda Atsushi 東京大学, 大学院総合文化研究科, 准教授 (00731556)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: ガラス転移 / ジャミング転移 / エネルギー地形

Outline of Final Research Achievements

Glass is the matter in which particles get frozen with disordered structure. This work aims to classify a variety of glassy matters and understand the "defect" of glasses. To this end, this focused on the analysis of the complex energy landscape of glassy systems. We performed researches for three years along this line, and obtained the following key results: (1) we found and quantified the quasi-localized low frequency vibrations of glasses, (2) we found and quantified the slow relaxation mode in athermal jammed matters, (3) we unveiled the nature of the jamming transition of anisotropic dimer particles, (4) we found peculiar low frequency vibrations of physical gels with competing interactions, (5) we constructed a mean-field theory of multi-component glasses, and (6) we introduced a model of bacterial cytoplasm, where the active forces fluidize the glassy states.

Free Research Field

化学物理、統計力学

Academic Significance and Societal Importance of the Research Achievements

我々の身の回りには、結晶のような粒子が整列した固体だけでなく、乱れた構造を持った固体が多数ある。これらの系をガラスと呼ぶ。本研究では、とくにこれらの物質のエネルギー地形に注目して、多彩なガラスの示す異常な物性を理解することを目指した。研究の結果、ガラスが特異な「欠陥」を持つことやその定量的な特徴を明らかにしたほか、ガラス系の遅い緩和モードの同定や、異方性粒子・物理ゲル・バクテリア細胞質などにガラス系の理解を展開することに成功した。