Quantum mechanical modelling of steady state photoconductive behaviour of AlGaAs/GaAs QWIP at varying bias and optical density

A quantum mechanical approach of first order born approximation is taken to numerically model AlGaAs/GaAs Quantum Well Infrared detector that operates at long wavelength region (8-9μm). Our numerical analysis of the photocurrent spectra as well as the broadening of the same at 8.31μm peak wavelength is found to be in close resemblance with the experimental result with 8.55μm peak wavelength as reported by Alves et. al. We have gone one step further by subsequently exploring the photo-response behavior of QWIP at the limit of strong electron-photon interaction and found that, besides the modification in photo-current spectrum in terms of relative magnitude and spectral shift, the strong non-linear photo-response enforced by light-matter coupling possesses the potential of accommodating multi-color detection mechanism under moderate bias and high optical density in active region.