Current limiting effects of photoactivated charge domain in semi-insulating GaAs photoconductive switch

The photoactivated charge domain (PACD) plays an important role in the nonlinear modes of semi-insulating GaAs and LnP photoconductive switches. The formation and transporting process of photoactivated charge domain are discussed in this paper, which indicate that it is the shielded electric field that induced the unique distribution and evolution law of the PACD. The PACD restricts space-charge current in the photoconductor and the output current of the photoconductive switch by its shielded effect.