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Photoluminescence is one of the most used spectroscopy techniques for the study of the optical properties of semiconducting materials and heterostructures. In this work the potentiality of this technique is explored through the investigation and characterization of structural imperfections originated from fluctuations in the chemical composition of ternary and quaternary alloys, from interface roughnesses, and from unintentional compounds formed by the chemical elements intermixing at the interfaces. Samples of GaAs/AlGaAs, GaAsSb/GaAs, GaAsSbN/GaAs and GaAs/GaInP quantum well structures are analyzed to verify the influence of the structural imperfections on the PL spectra

The reflectivity of a Bragg mirror composed by materials of the antimony family (AlGaAsSb/AlAsSb), doped with tellurium, is analyzed in this work. The sample was prepared by molecular beam epitaxy (MBE) and the reflectivity was measured by Fourier Transform Infra-Red Spectroscopy (FTIR). In order to discuss the Bragg mirror properties, the experimental reflectivity is compared to a simulation of the reflectivity based on the matrix formalism.