2-D electro-optic sampling in GaAs photoconductive switches

The electro-optic imaging system has been used to observe the dynamics of photoconductive switching in GaAs. GaAs has two distinct regions of operation. At biases below 3-6 kV/cm (depending on material preparation) the switches behave in a simple fashion. The field collapses with the integral of the absorbed light and then recovers as the carriers recombine. Above 6 kV/cm the electric field across the switches exhibit transient anomalies. This technique could also be used for other semiconductor devices such as integrated circuits.