Non-linear optical properties of TeO2-based glasses: ab initio static finite-field and time-dependent calculations

Abstract Ab initio calculations of the non-linear optical properties for the TeO 4 and TeO 3 structural units in TeO 2 -based glasses are presented. Time-dependent Hartree–Fock calculation below the frequency of ∼400 THz (750 nm) shows that the shorter wavelength of the light injected should lead to the higher non-linear optical responses in both TeO 4 and TeO 3 structural units. Static finite-field calculation with the localized molecular orbital analysis classifies the second hyperpolarizability by the electron pairs assigned to the chemical bonds. This analysis suggested that the lone pair of electrons on the Te atom is a key to the non-linear optical properties of the TeO 2 -based glasses and that the TeO 4 structural unit is responsible for the higher non-linear optical properties rather than the TeO 3 .