Optical properties of the compounds BaTiO and SrTiO

BaTiO and SrTiO are ceramic materials having immense technological applications. We present state-of-the-art calculations of the frequency-dependent dielectric function using the full potential linear augmented plane wave method. We find that compared to the previous calculations, our calculations show better agreement with the experimental data. We studied BaTiO in both the room-temperature tetragonal and high-temperature cubic phase. The calculated optical properties for the tetragonal phase are found to be in better agreement with experiment as compared to those for the cubic phase. The effect of tetragonality on band structure and density of states is found to be very small, while it is significant for the optical properties. The calculated results for the room-temperature cubic phase of SrTiO also are in much better agreement with experiment than previous calculations. © 2004 The American Physical Society.