Computational design of metamorphic In(N)AsSb mid-infrared light-emitting diodes

We present a theoretical investigation of the optical properties of metamorphic InNy(As1-xSbx)(1-y)/AlzIn1-zAs type-I quantum wells (QWs) designed to emit at mid-infrared wavelengths. The use of AlzIn1-zAs metamorphic buffer layers has recently been demonstrated to enable growth of lattice-mismatched InAs1-xSbx QWs having emission wavelengths greater than or similar to 3 mu m on GaAs substrates. However, little information is available regarding the properties of this newly established platform. We undertake a theoretical analysis and optimisation of the properties and performance of strain-balanced structures designed to emit at 3.3 and 4.2 mu m, where we recommend the incorporation of dilute concentrations of nitrogen (N) to achieve emission beyond 4 mu m. We quantify the calculated trends in the optical properties, as well as the ability to engineer and optimise the overall QW performance. Our results highlight the potential of metamorphic InNy(As1-xSbx)(1-y)/AlzIn1-zAs QWs for the development of mid-infrared light-emitting diodes, and provide guidelines for the growth of optimised structures.