Advanced Development of the Multi-Hundred Gigahertz Electro-Optic Modulator andPhotodetector

摘要

The project was established to develop materials and structures for modulationand detection of multi-hundred-GHz signals. During the period of three years we have fabricated and tested modulators using bulk GaAs and Si overgrowth on GaAs. We have also developed a probe sensitive to greater than 100 GHz signals with 100 nm spatial resolution. This probe has since been extended to a minimum detectable voltage sensitivity of a few nanovolts per square root hertz. We made high-speed measurements of photoconductive response in Er:GaAs showing it to have a carrier lifetime varying from 22 ps to 3.1 ps with doping from 10(exp 19)/cu cm to 10(exp 20)/cu cm. Finally, we made photoconductive sweep-generating switches for jitter free streak camera development.