Dual THz emissions of GaAsBi for THz photoconductive switching

We have measured dual THz emissions from GaAsBi-based photoconductive (PC) switches. Such consecutive emissions triggered by a single excitation pulse are caused by dual carrier lifetime previously reported for this material. The study investigates the variation of such emissions with different material growth conditions such as Bi percentage and annealing temperature. Measured results reveal a notable contrast of the effect of such property in THz emitting and THz receiving applications of PC switches.