Numerical analysis of the emission properties of terahertz photoconductive antenna by finite-difference-time-domain method

The emission properties of terahertz(THz) photoconductive antenna (PCA) have been numerically studied by three-dimensional finite-difference-time-domain method based on the full-wave model. The dependence of the THz radiation on various parameters, such as laser power, bias voltage, substrate's material, pulse duration of the laser, beam spot's size, dimension of the antenna, were comprehensively simulated and analyzed. This work, on one hand, reveals the internal relationship between the THz radiation of a PCA and the involved parameters, so that one can have a better understanding of the PCA. On the other hand, it can inspire new PCA's design that aims at improved performance, such as high radiation power, enhanced optics-to-THz conversion efficiency, and broadband spectrum.