Single photon emission from positioned GaAs/AlGaAs photonic nanowires

Positioned AlGaAs nanowires with an embedded axial heterostructure GaAs quantum dot (QD) on a prepatterned substrate have been grown. The geometry of the nanowires allows for an outcoupling of the emitted light through the nanowire tip and thereby to probe a single nanowire directly on the growth substrate. Single QD linewidths as small as 95 μeV and photon antibunching were observed at continuous wave laser excitation with a second order autocorrelation function g(2)(0)=0.46. The results represent an attractive bottom-up fabrication approach for the realization of high efficiency photonic wire based single photon sources.