Band gaps and refractive indices of AlGaAsSb, GaInAsSb, and InPAsSb: Key properties for a variety of the 2–4-μm optoelectronic device applications

The methods for calculation of material parameters in compound alloys are discussed, and the results for AlxGa1−xAsySb1−y, GaxIn1−xAsySb1−y, and InPxAsySb1−x−y quaternaries lattice matched to GaSb and InAs are presented. These quaternary systems may provide the basis for optoelectronic devices operating over the 2–4-μm wavelength range. The material parameters considered are: the lattice constant, the lowest direct- and indirect-gap energies, and the refractive index. The model used is based on an interpolation scheme, and the effects of compositional variations are properly taken into account in the calculations. Key properties of the material parameters for a variety of optoelectronic device applications are also discussed in detail.