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arXiv · 1503.07141

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

Luca Sapienza·Marcelo Davanco·Antonio Badolato·Kartik Srinivasan
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Abstract

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

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Luca Sapienza, Marcelo Davanco, Antonio Badolato, Kartik Srinivasan. 2015-08-05. Nanoscale optical positioning of single quantum dots for bright and pure single-photon emission. https://doi.org/10.1038/ncomms8833

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