Investigation of fast risetime bulk GaAs photoconductive switches with two opposite gridded electrodes

Investigations of fast switching mechanisms in high-power bulk GaAs photoconductive switches with two opposite electrodes were conducted using conventional and optical probe techniques. Although slow risetime laser light from a solid-state laser array was used to trigger a 2 mm long photoconductive GaAs switch, it was shown that with sufficient voltage amplitude, subnanosecond risetime pulses could be produced. Utilizing an electrooptic imaging system, dynamic electric field profiles under laser light illumination were obtained which confirmed the faster response of the two-sided switch. It is concluded that the experimental results obtained using both conventional and optical probe techniques may provide substantial clues as to a possible nondestructive avalanche mode of operation for these switches