In As Sb ∕ In P quantum dots for midwave infrared emitters: A theoretical study

Abstract

A theoretical study of the electronic properties of InAsSb quantum dots (QDs) deposited on InP substrate is presented. Unstrained bulk materials present a direct gap between 0.1and 0.35eV suitable for mid-infrared emitters (2–5μm). However, strain and quantum-confinement effects may limit the extension of the emission spectrum of these nanostructures towards the higher wavelengths. Various associations of materials in the barrier are considered. Among the possible associations, InAs0.5Sb0.5∕GaAs0.5Sb0.5 QDs may provide a low-energy emission with a material system similar to the well-known InAs∕GaAs system. Other materials associations such as InAsSb∕InGaAsP∕InP are also studied. Band lineups, optical transitions, optical losses, and effective masses are computed and discussed.