Computation of dark current in QWIPs using a modelling based on Ehrenfest theorem

In this paper, we present a novel model to compute dark current in quantum well infrared photodetectors (QWIP) in the thermionic regime, based on the Ehrenfest theorem and with no adjusting parameter. In this model, the quantum operator of linear momentum is used to obtain the carriers velocity above the barrier level. The wave functions are calculated considering non-parabolic approximation and temperature-dependent gap energy. The theoretical results are compared with experimental data obtained from conventional AlGaAs/GaAs QWIPs with rectangular wells and symmetric barriers. The results are in good agreement with experimental data at different temperatures in the thermionic regime. (paper)