Fourier-transform infrared photoreflectance spectroscopy of the InSb/InAs/In(Ga,Al)As/GaAs metamorphic heterostructures with a superlattice waveguide

Abstract

Fourier-transform infrared photoreflectance (PR) spectroscopy was used to study the energy spectrum of InSb/InAs/In(Ga,Al)As/GaAs metamorphic heterostructures with a superlattice waveguide at room temperature (RT). Theoretical calculations in the framework of the eight-band Kane model were performed to obtain a reliable knowledge of the actual energies of the most probable optical transitions. The experimental results were analyzed to determine the influence of the design features and stress balance on the energy spectra of the structures. Photoluminescence studies performed at 11 K and RT, as well as the determination of the internal quantum efficiency of luminescence, enabled us to characterize the emission characteristics of the structures, regardless of their waveguide efficiency. The structure with a 5-nm-thick GaAs insertion within the metamorphic buffer layer exhibited the highest probability of the main optical transition observed in the PR spectra as well as the highest luminescence intensity and quantum efficiency.