Voltage Tunable Dual-Band Quantum-Well Infrared Photodetector for Third-Generation Thermal Imaging

We investigate the theoretical calculations of the voltage tunable dual-band quantum-well infrared photodetector (QWIP) in the long and very long wavelength infrared range (LWIR and VLWIR). The detector consists of two serially connected GaAs/AlGaAs stacks which have spectral responses of 8.4- and 14- μm wavelengths, respectively. The peak responsivity wavelength of the stacks shifts from 8.4 to 14 μm as the bias voltage is increased.