Enhancing the THz emission through surface patterning in Photo-Conductive Antenna

In this article we have investigated the effect of surface nano-patterns in THz Photo-Conductive Antennae (PCA). The surface patterns help to localize the incident IR excitation thus reduces the reflection. It also reduces carrier recombination time by introducing defect states in current path. The combined effect enhances the THz emission from the device up to 220% when the electrical bias field is parallel to the optical pump polarization.