A further study of THz photoconductive antennas

For the terahertz (THz) wave generation and reception (detection), photoconductive antennas are the most wisely used antennas. In this paper, a further study of such an antenna is undertaken. It is linked to two distinct types of THz systems (broadband pulse type and narrowband continue wave type). The major differences in requirements and design considerations between them are identified and investigated. The main focus of the paper is on how to improve the antenna radiation efficiency which is at the moment still a very challenging issue. We have used both analytical and numerical approaches to study this subject. Some interesting results are obtained and compared with measured ones, and reasonable agreements are obtained. These results are useful to gain a better understanding of THz photoconductive antennas and should also be useful for designing THz antennas with improved radiation efficiency.