Near-red emission from site-controlled pyramidal InGaN quantum dots

We have fabricated InGaN nanostructures on top of GaN hexagonal pyramids by selective metalorganic vapor-phase epitaxy. With this approach, we are able to exactly control the position of the emitting quantum dot, which is an essential requirement for functionalized single-photon emitters. The emission properties as well as the relaxation and recombination mechanisms were investigated using spectroscopic methods. Regions of different confinement were identified, with the photoluminescence emission from the InGaN quantum dots around $2.03eV$ and a decay time of $1.4ns$⁠. The constant temperature behavior of the radiative decay time confirms its zero-dimensional character. Spatially resolved cathodoluminescence measurements attribute this emission to the apex of the pyramid.