A many-body model based on the self-consistent screened Hartree–Fock approximation is used to study the electron-electron exchange interaction effect on the dark current in n-type AlxGa1-xAs/GaAs multiple quantum wells infrared detectors. This is accomplished by taking the difference between the dark current calculated from the single-particle model and that obtained from the many-body model. This difference is found to be independent of the electron mobility and the saturation velocity. The difference in the dark current was studied as a function of the bias voltage, doping concentration, and temperature. The results predict 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.© 1997 American Institute of Physics.