THz time-domain spectroscopy of electro-optic crystals

We investigate the optical properties of the nonlinear crystals LiNbO/sub 3/, LiTaO/sub 3/, ZnTe and CdTe in the far infrared regime. Using terahertz time-domain spectroscopy (THz-TDS) we have measured the complex frequency response up to 3 THz (100 cm/sup -1/) for these electro-optic crystals with high accuracy (<0.5%). The data are interpreted with a simple Lorentzian oscillator model. Additional absorption features have been found.