Single-photon emission from InGaAs quantum dots grown on (111) GaAs

Stock, Erik; Warming, Till; Ostapenko, Irina; Rodt, Sven; Schliwa, Andrei; Töfflinger, Jan Amaru; Lochmann, Anatol; Toropov, Aleksandr I.; Moshchenko, Sergej A.; Dmitriev, Dimitry V.; Haisler, Vladimir A.; Bimberg, Dieter

Inst. Festkörperphysik

In this letter, we demonstrate that self-organized InGaAs quantum dots (QDs) grown on GaAs (111) substrate using droplet epitaxy have great potential for the generation of entangled photon pairs. The QDs show spectrally sharp luminescence lines and low spatial density. A second order correlation value of g(2)(0)<0.3 proves single-photon emission. By comparing the power dependence of the luminescence from a number of QDs we identify a typical luminescence fingerprint. In polarization dependent microphotoluminescence studies a fine-structure splitting ranging ≤40𝜇eV down to the determination limit of our setup (10𝜇eV) was observed.