High-temperature Brillouin scattering in fused quartz

Abstract

Thermal Brillouin scattering has been studied in fused silica from room temperature, through the glass transition temperature (1200°C), and up to near the melting temperature of quartz (∼1700°C). The shear and longitudinal Brillouin shifts, the longitudinal linewidth, Pockel's coefficient, and the Landau‐Placzek ratio are measured. From these the behavior of the elastic moduli and absorption coefficient with temperature are obtained. A significant change in the temperature dependence of the moduli and Pockel's coefficient is found to occur above 500°C. In addition, by using the Landau‐Placzek ratio the first measurement in fused quartz of the equilibrium static compressibility above the glass transition has been obtained. Surprisingly little temperature dependence is observed.