Three Dimensional Radiation Feature Calculation for Terahertz Photoconductive Antenna Based on FDTD Method

Abstract

It is photoconductive antenna for terahertz generation and detection to be applied widely as a radiation resource. It has a significant application prospect in many areas such as terahertz imaging, spectrum detection and so on. In this paper, we proposed a 3-D radiation feature calculation method for terahertz photoconductive antenna using Finite Difference Time Domain (FDTD), and elaborated the influence of semiconductor drift current, diffusion current to electromagnetic field based on the radiation principle of photoconductive antenna. According to actual application condition, we simplified drift equation and continuity equation, and obtained the iteration equation of current density, electric field and magnetic field, and at last, we illustrated a calculation flow of radiation properties of photoconductive antenna.