A Comparison of the Performance of THz Photoconductive Antennas

This letter explores the influence of the geometry of bias electrodes in the performance of terahertz (THz) photoconductive antennas (PCAs). To this end, a methodology is presented to calculate numerically the operational bandwidth and radiation efficiency of the PCAs. The procedure is validated through a comparison to experimental measurements. Also, results are depicted from numerical simulations of different PCAs under varying conditions of bias voltage, doping factor, and incident optical power. It is concluded that an appropriate configuration of the electrodes may double the efficiency of the antennas, with a penalty in the bandwidth of the radiated pulse usually smaller than 10%.