%A Tianyi WANG,Zhengang YANG,Si ZOU,Kejia WANG,Shenglie WANG,Jinsong LIU %T Time behavior of field screening effects in small-size GaAs photoconductive terahertz antenna %0 Journal Article %D 2015 %J Front. Optoelectron. %J Frontiers of Optoelectronics %@ 2095-2759 %R 10.1007/s12200-015-0488-9 %P 98-103 %V 8 %N 1 %U {https://journal.hep.com.cn/foe/EN/10.1007/s12200-015-0488-9 %8 2015-02-13 %X

The field screening effects in small-size GaAs photoconductive (PC) antenna are investigated via the well-known pump and probe terahertz (THz) generation technique. The peak amplitude of the THz pulses excited by the probe laser pulse as a function of the pump-probe time delay was measured. An equivalent-circuit model was used to simulate the experimental data. Based on the good agreement between the results of simulation and experiment, the time behavior of the radiation and space-charge fields was simulated. The results show that the space-charge screening dominantly determines the device response in the whole time, while the radiation filed screening plays a key role in initial time which strongly affects the peak THz field. The parameter analysis was performed, which may be valuable on the optimum design for the antenna as a THz emitter.