Two-color GaAs/(AlGa)As quantum well infrared detector with voltage-tunable spectral sensitivity at 3–5 and 8–12 μm

Abstract
We report on a novel GaAs:Si/(AlGa)As multiquantum well photodetector structure which exhibits photoresponse maxima in both the 8–12 and 3–5 μm spectral regions. The relative intensity of these maxima strongly depends on the bias voltage, demonstrating the potential of such a structure as a tunable two-color intersubband detector.