Physical and optical properties of zinc arsenic tellurite glasses

Glasses in the system xZnF2-(20−x)ZnO-40As2O3-40TeO2 (x = 0, 4, 8, 12, 16 and 20 mol%) were prepared by normal melt quenching method. The change in density and ionic packing density in these glasses indicates the effect of ZnF2 on the glass structure. The optical constants of these glasses are determined over a spectral range, providing the complex dielectric constant to be calculated. The values of the optical band gap Eg for all types of electronic transitions and refractive index have been determined and discussed. The optical parameters such as N/m∗, ε∞, ωp, Ed and E0 have been estimated. The values of N/m∗ reflect an increase in the free carrier concentration with increasing ZnF2 content. This leads to an increase in the reflectance, R which in turn increases the refractive index.