Reviewing quantum dots for single-photon emission at 1.55 µm: A quantitative comparison of materials

Abstract

In this work, we present a review of quantum dot (QD) material systems that allow us to obtain light emission in the telecom C-band at 1.55 µm. These epitaxial semiconductor nanostructures are of great technological interest for the development of devices for the generation of on-demand quanta of light for long-haul communication applications. The material systems considered are InAs QDs grown on InP, metamorphic InAs/InGaAs QDs grown on GaAs, InAs/GaSb QDs grown on Si, and InAsN QDs grown on GaAs. In order to provide a quantitative comparison of the different material systems, we carried out numerical simulations based on envelope function approximation to calculate the strain-dependant energy band profiles and the associated confined energy levels. We have also derived the eigenfunctions and the optical matrix elements for confined states of the systems. From the results of the simulations, some general conclusions on the strengths and weaknesses of each QD material system have been drawn, along with useful indications for the optimization of structural engineering aiming at single-photon emission in the telecom C-band.