Site-controlled growth of InP/InGaP quantum dots

We report on site-controlled growth of InP/InGaP quantum dots (QDs) on GaAs substrates. Shallow nanoholes etched into a InGaP layer are used as nucleation sites for the QDs. Optimized growth conditions and the use of strain mediated nucleation allow us to realize QD arrays with excellent long range ordering on hole pitches as large as 1.25 μm. Single QD lines with an average linewidth of 553 μeV and best values below 200 μeV are observed. Second-order photon-autocorrelation measurements show clear single photon emission with g(2)(0)=0.13±0.01.