Delay time in GaAs high-power photoconductive switches

The delay time defined as the time interval between the beginning of optical illumination and the onset of switching in photocurrent in gallium arsenide (GaAs) high-power photoconductivity switches is studied on the basis of electroabsorption caused by absorption edge shifting due to bandgap narrowing. The influences of the initial open-state field, the laser wavelength and the temperature are given. The results show it is the reflection and the transmission of the switch semiconductor slab indicated by the absorption fraction express the absorption rate of the illumination energy by the switch.