Enhancement of light emission from single quantum dot in photonic crystal nanocavity by using cavity resonant excitation

The authors demonstrate highly efficient selective excitation of a single InGaAs self-assembled quantum dot (QD) embedded in a photonic crystal defect nanocavity. A single QD, whose first excited state is resonant with the cavity mode resonance, shows strong light emission from the ground state under cavity resonant excitation. The light emission is nearly ten times stronger than that of a single QD located at an unpatterned area. This result is attributed to the local enhancement of the effective absorption by the cavity resonant effect. This highly efficient excitation technique can be useful for single photon sources.