Single photon emission in the red spectral range from a GaAs-based self-assembled quantum dot

Low temperature micro-photoluminecence and second-order single photon correlation experiments were performed on individual self-assembled In0.47Al0.34Ga0.19As/Al0.3Ga0.7As/GaAs quantum dots emitting in the range of 680–780 nm. Emission lines originating from exciton, biexciton, and charge exciton confined in the same dot could be identified. The derived exciton fine structure splitting is ∼125 μeV, whereas the biexciton and charge exciton binding energies are ∼4 and ∼9 meV, respectively. The photon correlation statistics measured for the exciton emission exhibited a clear antibunching with the value of gX−X2(0)=0.30±0.05, confirming unambiguously that such quantum dots act as true single photon quantum emitters.