Regions of different confinement in low-dimensional AlyIn xGa1-x-yN quantum structures

Abstract

The optical properties of metal-organic vapor phase epitaxy grown Al y In x Ga 1-x-y N quantum dot structures have been studied by time-resolved photoluminescence experiments. We investigated the recombination dynamics of the photo-exited carriers in dependence of the growth parameters such as aluminium flow and the duration of the growth interruption after the dot deposition. Our results confirm the presence of localized states, where the degree of localization is strongly dependent on the growth conditions. To describe this behavior, we propose a band structure with coupled potentials for these nanostructures. Finally, we demonstrate state filling to prove the zero-dimensional character of the strongly localized states in our quaternary quantum dots.