Ultrafast photodetectors with near-unity quantum efficiency

摘要

Abstract: We designed, fabricated and characterized Al$-x$/Ga$-1- x$/As/GaAs p-i-n resonant cavity enhanced (RCE) photodetectors with near-unity quantum efficiency. The peak wavelength is in the 780 - 830 nm region and post-process adjustable by recessing the top surface. Transit time limited bandwidth for these devices is in excess of 50 GHz. Possible applications of these detectors include conventional measurements of low light levels, quantum optical experiments that use pulsed sources and short-haul high speed communications. !10