Studies of physical phenomena in semiconductor nanostructures using samples with laterally nonuniform layers: Photoluminescence of tunneling-coupled quantum wells

Abstract

The previously suggested spectral-correlative method for studying nanostructures is applied to an analysis of photoluminescence of tunneling-coupled and isolated quantum wells in structures with laterally nonuniform layers. This method made it possible to use a single wafer to study the dependences of intensities of photoluminescence lines and their energy positions on the tunneling-barrier width for a system of tunneling-coupled GaAs-InGaAs-GaAs wells and on the quantum-well widths in a system of isolated AlGaAs-GaAs-AlGaAs quantum wells. Good agreement between the results of calculations and experimental data can be attained if it is assumed that a constant transverse electric field affecting the processes of trapping of charge carriers by quantum wells exists in a structure with tunneling-coupled quantum wells. The dependence of photoluminescence parameters on the width of isolated quantum wells is sensitive to the profile of heterointerfaces and to the processes of trapping the charge carriers by quantum wells.