A site-controlled quantum dot system offering both high uniformity and spectral purity

In this letter we report on the optical properties of site-controlled InGaAs quantum dots with GaAs barriers grown in pyramidal recesses by metalorganic vapor phase epitaxy. The inhomogeneous broadening of excitonic emission from an ensemble of quantum dots is found to be unusually narrow, with a standard deviation of 1.19 meV and the spectral purity of emission lines from individual dots is found to be very high (18–30 μeV), in contrast with other site-controlled dot systems.