Intrinsic Brillouin Linewidths and Stimulated Brillouin Gain Coefficients in Glasses studied by Inelastic Light Scattering

Rayleigh–Brillouin scattering measurements on various multicomponent halide glasses and some selected oxide glasses were done. The Brillouin linewidth measurements, the Brillouin intensities and frequency shifts allowed the calculation of phonon attenuation, Pockels' elastooptic coefficients and the Stimulated Brillouin scattering gain coefficients. Brillouin linewidths obtained experimentally range between the limit of 52MHz for a BeF2 glass and 213MHz for a Zirconium–Barium–Lanthanium–Fluoride glass.1 The parameter obtained in the above study shows that the threshold power for the onset of Stimulated Brillouin scattering in some halide glasses is greater than that for silicate glasses, which has important ramifications as a selection criterion for halide based glasses as single mode optical waveguide materials.2