Importance of the localization for inter-subband scattering rates in quasi two-dimensional structures

摘要

The inter-subband scattering in quasi two-dimensional heterostructures is critically examined in the case of cascade structures with a double well design. We show that when two kinds of elastic scatterers are present, the scattering frequencies may markedly differ from the one evaluated for plane wave states for the in-plane motion at the Born approximation. We argue that this feature results from the disorder-induced spatial localization of the eigenstates in the layer plane. The scatterer location dependence of the scattering frequencies is also discussed. At low concentration the in-plane localization is found to increase the inter-subband scattering.