Theory of vertical and lateral Stark shifts of excitons in quantum dots

Abstract

We present charge self-consistent 8-band k · p calculations of the quantum confined Stark shift of excitons for self-assembled buried InGaAs quantum dots. Many different shapes and alloy profiles of the dots have been systematically studied. We predict the Stark shift of excitons for simultaneously applied vertical and lateral electric fields, taking into account realistic alloy profiles in the quantum dot. The study of the Stark shift of neutral excitons and in both vertical and lateral electric field directions provides a wealth of information about the coupling of the exciton to external perturbations. We show that the combination of lateral and vertical electric fields provides a particularly sensitive probe of the dot shape and alloy composition.