Glass structure and light scattering

Elastic and inelastic light scattering experiments are performed on silica, SiO2, with OH content <20 ppm. Quantitative comparison is made between Raman, Brillouin and Rayleigh scattered intensities showing that for an accurate comparison Raman scattering has to be considered. The decrease of the Rayleigh scattering and the shift of the Boson peak with the decrease of the fictive temperature are attributed to two types of inhomogeneities typical of the structure of glass: frozen density fluctuations and elastic constant fluctuations in domains with dimensions ∼1 nm.