Nanoscale optical positioning of single quantum dots for bright and pure single-photon emission

• DOI: 10.1038/ncomms8833
• Publication Date: 2015-07-27T10:09:51Z
• Authors: Luca Sapienza; Marcelo Davanço; Antonio Badolato; Kartik Srinivasan
• Keywords: Single-Photon Source; Numerical aperture

Abstract Self-assembled, epitaxially grown InAs/GaAs quantum dots (QDs) are promising semiconductor emitters that can be integrated on a chip for variety of photonic information science applications. However, self-assembled growth results in an essentially random in-plane spatial distribution QDs, presenting challenge creating devices exploit the strong interaction single QDs with highly confined optical modes. Here, we present photoluminescence imaging approach locating respect to alignment features average position uncertainty <30 nm (<10 when using solid-immersion lens), which represents enabling technology creation optimized QD devices. To end, create single-photon sources, based circular Bragg grating geometry, simultaneously exhibit high collection efficiency (48%±5% into 0.4 numerical aperture lens, close theoretically predicted value 50%), low multiphoton probability ( g (2) (0) <1%), and significant Purcell enhancement factor (≈3).