Research Interests

I am using theoretical and computational approaches in characterization and materials design of glasses. The main technique employed is quantum-chemical calculations using clusters of atoms that model the local- and intermediate-range structures of glasses. Our research activities have demonstrated that the present theoretical approaches can achieve a level of sophistication that brings them on a par with experimental techniques of investigation concerning the molecular-level structure, electronic structure, and dynamics of glasses. In particular, our recent results have provided a quantitative foundation for a set of ideas about the well-known low-frequency anomalies in glasses and its relation to the glass transition that have been previously proposed before, but never yet properly substantiated at a molecular scale. Furthermore, present and recent results have raised some novel ideas concerning the defects in glasses, which will stimulate new thinking in the filed of photochemical reactions in disordered materials.

Research Subjects

• Structure and formation mechanism of defect centers in amorphous solids
• Structure and vibrational properties of glasses and glass forming liquids
• Dynamics of glass transition
• Structural modification of amorphous nano-particles under pressure

Selected Publications

◆T. Uchino and D. Okutsu, "Broadband Laser Emission from Color Centers Inside MgO Microcrystals," Phys. Rev. Lett. 101(11), 117401 (4 pages) (2008).

◆T. Uchino, A. Aboshi, T. Yamada, Y. Inamura and Y. Katayama, "In situ x-ray Diffraction Study of the Size Dependence of Pressure-Induced Structural Transformation in Amorphous Silica Nanoparticles," Phys. Rev. B 77(13), 132201 (4 pages) (2008).

◆N. Sagawa and T. Uchino, "Effect of Annealing on the Visible Photoluminescence Characteristics of Octadecyltrichlorosilane Monolayers on Silica Surfaces," J. Phys. Chem. C 112(12), 4581-4589 (2008).

◆T. Yamada, M. Nakajima, T. Suemoto, T. Uchino, "Formation and Photoluminescence Characterization of Transparent Silica Glass Prepared by Solid Phase Reaction of Nanometer-Sized Silica Particles," J. Phys. Chem. C 111(35), 12973-12979 (2007).

◆E. Koyanagi and T. Uchino, "Evolution Process of Luminescent Si Nanostructures in Annealed SiOx Thin Films Probed by Photoconductivity Measurements," Appl. Phys. Lett. 91(4), 041910 (3 pages) (2007).