Absorption and emission spectra of InAs/Ga1-xInxSb/AlSb nanostructures forinfrared applications

We report an empirical pseudopotential study of the optical properties of s everal InAs/GaSb superlattice structures, some of these additionally contai ning Ga1-xInxSb and AlSb layers, designed for infrared (IR) applications. T he optical absorption and emission spectra of these nanostructures are mode lled, with a view to establishing a quantitative link with the microscopic signature of the interface. The emission spectra of the structures having l aser applications are investigated for various population inversions. We ga uge the role of atomic disorder and determine the degree of alloy layer dis order for which the virtual crystal (VC) approximation provides an adequate description of the overall lineshape. An analogous study was carried out f or structures having applications as detectors. We find good agreement betw een the experimental absorption spectra and our computer model, and investi gate the effects of Auger recombination on device performance. (C) 2000 Els evier Science B.V. All rights reserved.