高圧力下における SiO₂ ガラスの振る舞い

抄録

The high-pressure behavior of SiO₂ glass has attracted considerable attention because of its importance not only in condensed-matter physics and materials science but also in geophysics. We have conducted X-ray absorption/diffraction measurements and optical-microscope observation to understand the behavior of SiO₂ glass under hydrostatic and uniaxial compression. SiO₂ glass undergoes pressure-induced structural transformations first in the intermediate-range order (the network structure consisting of SiO₄ tetrahedra) and then in the short-range order (the coordination number). Under uniaxial compression, the atomic arrangement in intermediate-range order deforms largely and a large differential strain remains after decompression. This article attempts to review these interesting behaviors, mainly based on our recent researches.