Enhancement of the intensity and bandwidth of terahertz radiation in photoconductive dipole antennas

Abstract

In this paper, in order to amplify terahertz output pulses and achieve higher frequency peaks, a scheme of spiral lines is proposed to be used in the electrodes of photoconductive dipole antennas. This scheme is simulated with the help of the CST software. At first, a photoconductive antenna is simulated and compared with the experimental results. In order to improve the effectiveness of the antenna, certain changes are made in its shape. These changes are necessary because the intensity and frequency bandwidth of terahertz radiation in photoconductive antennas are less effective than other sources of terahertz waves and the shape of electrodes plays a fundamental role in the output of the radiation. As a result, adding spiral lines to antenna electrodes increases the intensity of terahertz radiation and shifts the frequency peak of that radiation toward higher frequencies.