Atomistic pseudopotential theory of optical properties of exciton complexes in InAs/InP quantum dots

The photoluminescence (PL) spectra of exciton complexes in quantum dots (QDs) are of primary importance to understand their optical properties, which are well understood in InAs/GaAs QDs both theoretically and experimentally. However the knowledge can not be directly applied to InAs/InP QDs. In this work, we investigate the differences of the PL spectra of the two dots using an empirical pseudopotential method. The alignment of exciton complex transition lines of the two QDs are very different and the reasons are explained. We show that the “hidden” correlation energies in InAs/InP QDs are smaller than those in InAs/GaAs QDs and the lifetime of exciton complexes in InAs/InP QDs are about twice longer than those in InAs/GaAs QDs.