Bound-to-Quasi-Bound Quantum-Well Infrared Photodetectors

Multiple-quantum-well AlxGa1 - xAs photodetectors that exploit transitions of electrons from quantum-well bound states to quasi-bound states are undergoing development for use at wavelengths from 6 to 25 µm. These photodetectors are intended to provide detectivities that are higher (signal-to-noise ratios that are higher) than those of predecessor quantum-well infrared photodetectors that exploit transitions of electrons from bound to continuum states.