Electro-optic detection of THz radiation in LiTaO3, LiNbO3 and ZnTe

Freely propagating THz pulses are detected in electro-optic (eo) crystals by monitoring the phase retardation (PR) of an infrared femtosecond probe pulse. This technique permits the determination of the temporal shape of the THz pulse in the subpicosecond time domain. We present measurements in ${\mathrm{LiTaO}}_3$ , ${\mathrm{LiNbO}}_3$ , and ZnTe and compare their signal performance as eo crystals with theoretical calculations for the PR signal. ZnTe shows the best performance for eo detection.