Triggering GaAs photoconductive switches with 1064nm laser

The GaAs photoconductive switch is triggered by 1064 nm laser pulses with the optical energy of 0.05 mJ and 0.3 mJ respectively, under a bias 500 V, the electrode gap of the switch is 3 mm. The output electrical pulse waveforms show that the photoconductivity can occur in semi-insulating GaAs photoconductive switch at 1064 nm. Some possible absorption mechanisms have been discussed for GaAs triggered by 1064 nm, and the two step photoabsorption with EL2 defect is suggested as the primary process for the photoconductivity.