The Institute of Scientific and Industrial Research, Osaka University


LAST UPDATE 2021/06/16

  • 研究者氏名
    Researcher Name

    白井光雲 Koun SHIRAI
    准教授 Associate Professor
  • 所属
    Professional Affiliation

    The Institute of Scientific and Industrial Research, Osaka University

    Department of Theoretical Nanotechnology
  • 研究キーワード
    Research Keywords

    First-principles electronic calculation
    Materials search
    Thermodynamical study of glasses
Research Subject
Materials Search by First-Principles Calculations

研究の背景 Background


Today's role of the density-functional theory becomes more than the traditional role of theoretical work, namely, elucidation of material properties. We are able to use this theory to predict novel materials that have desirable properties to a particular application. We develop this method for real applications. Meanwhile the traditional role of elucidation of material properties is also persuaded. In particular, study of glass materials is a big challenge for theorists. This is because glass materials are considered as nonequilibrium materials to which usual thermodynamic methods are not applicable.

研究の目標 Outcome


Materials design based on DFT is developed. For practical application, structural prediction for boron crystals is carried out, owing to the recent interest in this system. For elucidation of material properties, the glass transition is studied. This study is interesting in that glass materials are presently considered to be in nonequilibrium state, for which usual methods of thermodynamics are not applicable. Hence, this problem is an important challenge to the current stutas of DFT.

研究図Research Figure

Fig.1. New structure of Cu complex in silicon. The Cu4 tetrahedron causes a strong photoluminescence line.

Fig.2. Phase diagram of tetragonal boron crystal. This diagram explains why the delta-orthorhombic phase can be obtained by help of hydrogenation.

Fig.3. Simulation of glass transition in specific heat versus temperature. Different rates of heating indicated  by numbers are used.

文献 / Publications

J. Phys.: Mater. 2 045004 (2019). J. Phys. Commun4, 085015 (2020). J. Phys. Commun. 5, 015004 (2021). Jpn. J. Appl. Phys. 60, 021001 (2021)