EXCHANGE INTERACTION EFFECT ON THE DARK CURRENT IN N-TYPE ALXGA1-XAS GAAS MULTIPLE-QUANTUM WELLS INFRARED DETECTORS/

A many-body model based on the self-consistent screened Hartree-Fock a pproximation is, used to study the electron-electron exchange interact ion effect on the dark current in n-type AlxGa1-xAs/GaAs multiple quan tum wells infrared detectors. This is accomplished by taking the diffe rence between the dark current calculated from the single-particle mod el and that obtained from the many-body model. This difference is foun d to be independent of the electron mobility and the saturation veloci ty. The difference in the dark current was studied as a function of th e bias voltage, doping concentration, and temperature. The results pre dict that the dark current obtained from the single-particle model is overestimated as much as an order of magnitude at low temperatures and high doping concentrations. (C) 1997 American Institute of Physics.