Theoretical investigation of terahertz pulses generated from ultrafast photoconductive switches

The technique of terahertz pulses generated from the photoconductive switches has been applied in the ultrafast electrical pulse metrology recently. A lumped-element theoretical model is established to describe the performance of the LT-GaAs ultrafast photoconductive switch used in the ultrafast pulse standard. Based on the model, waveforms and power spectrums of the generated terahertz pulses are calculated under 840 nm optical excitations. And comparisons between the theoretical results and the experimental results are carried out. © 2010 IEEE.