The influence of the fictive temperature and the OH content on the dynamical properties of vitreous silica: comparison of Raman, Brillouin, and neutron scattering spectra

We have performed new inelastic light and neutron scattering experiments on different samples of vitreous silica: Puropsil, Spectrosil, Tetrasil, Suprasil and Heralux commercial grade samples have been investigated by means of Raman and Brillouin light scattering and inelastic neutron scattering experiments. We have found significant changes in the density of states and in the sound velocity, which can be attributed to differences both in the fictive temperature and in the OH bonds present in the different samples.