Generation and detection of ultrabroadband terahertz radiation using photoconductive emitters and receivers

Abstract

We report the coherent generation and detection of ultrabroadband terahertz (THz) radiation using low-temperature-grown GaAs photoconductive antennas as both emitters and receivers. THz radiation with frequency components over 15THz was obtained, the highest reported for a THz time-domain system based on photoconductive antennas. Such a system has a smooth spectral distribution between 0.3 and 7.5THz, ideal for spectroscopic applications. In addition, sharp spectral features at 8.0 and 8.8THz were observed, and explained in terms of optical phonon resonances in the photoconductive antennas.