Scattering under the Rayleigh-Debye-Gans condition for transparent glass ceramics

We review the various theoretical relations that quantify light scattering under the Rayleigh-Debye-Gans (RDG) approximation and apply these relations to the calculation of scattering within Transparent Glass Ceramics (TGCs) composed of large nanocrystals within a glass matrix. For a more realistic picture of scattering, we include within these models material dispersion of the crystals and glasses across the transparency range of these materials by way of the Sellmeier equation. We first select a number of crystal-glass sets that are near index matched in the visible and near infrared in order to fulfill one of the RDG criterions. We find that the various forms of scattering under the RDG approximation differ significantly across the visible and near infrared. We also find that the inclusion of material dispersion changes significantly the trends in the calculated scattering cross section across the studied wavelength range. Overall, we find that the calculation of the scattering cross section is highly dependent on the chosen theoretical relation and that the inclusion of material dispersion is vital in order to achieve a clear picture of scattering loss of this new class of optical material.