Abstract

Low temperature molecular beam epitaxial (LT-MBE) growth of III-V compound semiconductors offers a unique approach for obtaining subpicosecond photoconductive response in these materials. We report the results on both InP and GaAs based material systems. External electrooptic sampling and femtosecond transient reflectivity measurements were used to characterize the photoexcited carrier response, which was observed to be of subpicosecond duration. Preliminary investigations of temperature dependent response suggest the possibility of shallow traps and/or amorphouslike behavior to be responsible for the electrical characteristics. The effect of the epitaxial growth conditions on the photoconductive response is also discussed.

© 1990 Optical Society of America