Optical absorption mechanism of GaAs photoconductive semiconductor switch

Abstract

The output charges of linear and nonlinear semi-insulating GaAs photoconductive semiconductor switches (PCSSs) triggered by a 1064 nm nanosecond pulse laser with an energy of millijoule level are measured under different bias voltages. On the basis of the operation mechanism of the linear PCSS, the photogenerated carrier densities of the PCSS are measured. From the results of the comparison between the measured values and the values determined by different absorption mechanisms, the absorption mechanism of the switch is analyzed. As an important parameter of the avalanching charge domain, the effect of the photogenerated carrier density on the output performance of GaAs PCSSs is discussed.