Wave-Function Topology Effects on Charged Excitons in Type-II InAs/GaAsSb Quantum Dots and Rings

Abstract

InAs self-assembled quantum dots capped with GaAsSb exhibit type-II band alignment and singly or doubly connected hole wave-function topology depending on the thickness of the capping layer or the Sb concentration. A configuration interaction analysis of the excitons complexes X0, X−1, and X+1 for different overlayer thicknesses is presented. A characteristic double line structure of the X+1 recombination is predicted for the doubly connected topology. A hallmark is established to identify the optical Aharonov–Bohm transition in addition to the well-known intensity fade-out of the X0.