Broadband asymmetric quantum-well infrared photodetector in long-wavelength infrared range (LWIR)

A theoretical investigation of a GaAs-AlGaAs infrared detector consisting of three asymmetric quantum wells is presented. Each quantum well is sensitive to yield absorption and a photoresponse at peak wavelengths of 8 mum, 9.5 mum and 10.8 mum respectively. Device operation is based on inter-subband bound-to-bound transition. Asymmetry in the quantum wells is shown to give broad band responsivity spectrum at an operating bias.