Detection of THz radiation by using GaAs in Cherenkov-phase-matched electro-optic sampling

We propose and demonstrate electro-optic (EO) sampling of terahertz (THz) radiation by using GaAs in the Cherenkov phase-matching scheme. This technique can be implemented without Si-prism coupling due to a small difference between optical group and THz phase refractive indices of GaAs and its low THz absorption.