Modeling of disorder influenced Auger recombination in strained-layer type-II superlattices

The effects of disorder on Auger recombination lifetimes in strained-layer type-II superlattices are estimated. Disorder is modeled in two ways: (i) by completely neglecting momentum conservation in Auger transitions, and (ii) by including phonon scattering in the transitions. The purpose of (i) is to obtain establish bounds on the effects of disorder, and of (ii) to provide more realistic lifetime estimates for high-quality materials. In both cases, the disorder is assumed to be less severe than what would cause significant changes in the electronic band structure. The complete relaxation of momentum conservation results in Auger lifetimes decreasing by approximately one order of magnitude. However, electron–phonon effects have a relatively small effect because the interaction is weak. Hence, the benefits of band engineering in such superlattices remain substantial even in the presence of typical disorder.