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arXiv · 1203.5676

Bright single-photon sources in bottom-up tailored nanowires

Michael E. Reimer·Gabriele Bulgarini·Nika Akopian·Moïra Hocevar·Maaike Bouwes Bavinck·Marcel A. Verheijen·Erik P. A. M. Bakkers·Leo P. Kouwenhoven·Val Zwiller
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Abstract

The ability to achieve near-unity light extraction efficiency is necessary for a truly deterministic single photon source. The most promising method to reach such high efficiencies is based on embedding single photon emitters in tapered photonic waveguides defined by top-down etching techniques. However, light extraction efficiencies in current top-down approaches are limited by fabrication imperfections and etching induced defects. The efficiency is further tempered by randomly positioned off-axis quantum emitters. Here, we present perfectly positioned single quantum dots on the axis of a tailored nanowire waveguide using bottom-up growth. In comparison to quantum dots in nanowires without waveguide, we demonstrate a 24-fold enhancement in the single photon flux, corresponding to a light extraction efficiency of 42 %. Such high efficiencies in one-dimensional nanowires are promising to transfer quantum information over large distances between remote stationary qubits using flying qubits within the same nanowire p-n junction.

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Michael E. Reimer, Gabriele Bulgarini, Nika Akopian, Moïra Hocevar, Maaike Bouwes Bavinck, Marcel A. Verheijen, Erik P. A. M. Bakkers, Leo P. Kouwenhoven, Val Zwiller. 2012-03-26. Bright single-photon sources in bottom-up tailored nanowires. https://doi.org/10.1038/ncomms1746

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