Nano photoconductive switches for microwave applications

This paper addresses the interaction between light wave technologies and semiconductors devices at the nanoscale. Research works aiming at the development of emerging 1D and 2D nano materials such as nanodots, nanowires, nanotubes and nanoribbons open the way to overcome the performances bottleneck of conventional microwave photoconductive switches. Such new materials offer new opportunities for the confinement of light/matter interaction and exhibit interesting energy band diagram in an optical wavelength spectrum covering visible to NIR. Strong material interests stays for the generation of very high local density of carriers in contrast with a high dark resistivity, in association with a high carrier mobility. These challenges can be reached today thanks to nanotechnology processes with a high compatibility constraint with submicrometer light coupling solutions and microwave devices and circuits technologies. Modeling and design tools dedicated to photoconductive effect description at nanometer scale, for its implementation in passive and active components must be set up in order to exalt this effect for microwave signal processing functionalities such as switching, generation, amplification and emission over a large frequency bandwidth. This paper will report on latest demonstrations of high performance photoconductive switches for high frequency applications at 0.8μm and 1.5μm based on LT-GaAs, GaAs nanowires and GaInAsSb semiconductor materials.