Accurate calculation of excited photocurrent in terahertz photoconductive antennas by using energy balance transport model

A photoconductive antenna (PCA) has been numerically investigated in the terahertz (THz) frequency band considering drift-diffusion and energy balance transport model. We will show that for high power applications, energy balance transport model become more accurate due to the consideration of carriers temperature. For this purpose, an optoelectronic solver, Silvaco TCAD software, is used to find an accurate absorbed optical intensity and optical carrier generation rate inside the fast photoconductive region through solving an optical scattering problem. Then, the equations governing the charge carrier transport inside the photoconductor are solved to obtain THz photocurrent by considering realistic material parameters.