ABSTRACT
The physics of transient and steady-state photoconductivity of quantum well infrared photodetectors (QWIPs) under localized illumination across QWIP structure (in the growth direction) is studied theoretically. Transient (non-equilibrium) responsivity is related to the sweep-out of the photoexcited carriers. Steady-state photoresponse is due to the formation of the dipole layer (DL) near the illuminated QW. Parameters of the DL and local steady-state and non-equilibrium responsivity for QWIPs with multiple QWs is calculated using analytical models. Local responsivity depends strongly on the coordinate of the illuminated QW and decreases from emitter to collector.
