Based On The Research Of Photoconductive Antenna Thz Wave Radiation

In the spectrum of Electromagnetics, THz band is the last unknown region for human. Photoconductive antenna is one of the most widely used THz sources. This article is mainly focused on improving the performance of THz wave emission from photoconductive antenna.Firstly, the development of THz technology and photoconductive antenna is introduced.In the followings, the pattern of photoconductive antenna, the application of femosecond laser and the principle of photoconductive antenna studied from quantum area and electromagnetics area is presented.Then the design of affording high biased voltage for photoconductive antenna is conducted and the results show that the THz radiation power is largely increased.Additionally, the method of separating antenna from transmission lines is proposed to improve the THz radiation performance. This method is proved to be widely used to many kinds of photoconductive antennas like dipole, bow-tie, Sierpinski fractal and H-fractal.In the end, the confused phenomena that the center frequency of THz pulse emission from dipole photoconductive antenna is not correspondence to the theory calculation results is explained by a new model. The calculation results of the model are similar to experimental results. What’s more, the new calculation of THz center frequency is proposed.