Modeling the capture probability and enhancing the photoconductive gain in quantum well infrared photodetectors (QWIPs)

In this work consideration is given to the dynamics of carriers in the continuum/quantum well systems and how this relates to the photoconductive gain of quantum well infrared photodetectors. In particular the quantum mechanical scattering theory approach, taking into account e-LO phonon and e-e scattering is invoked to evaluate the capture probability from the continuum into the quantum wells. It is shown that the capture probability P, is dependent on the quantum well width. The capture probability microscopic model is then utilized to introduce an additional tunnel barrier to disturb the continuum levels near the top of the quantum well. This induction enabled us to investigate the double-barrier improvements in the photoconductive gain. (C) 2003 Elsevier B.V. All rights reserved.