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arXiv · 2201.02465

A Pure and indistinguishable single-photon source at telecommunication wavelength

Beatrice Da Lio·Carlos Faurby·Xiaoyan Zhou·Ming Lai Chan·Ravitej Uppu·Henri Thyrrestrup·Sven Scholz·Andreas D. Wieck·Arne Ludwig·Peter Lodahl·Leonardo Midolo
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Abstract

On-demand single-photon sources emitting pure and indistinguishable photons at the telecommunication wavelength are a critical asset towards the deployment of fiber-based quantum networks. Indeed, single photons may serve as flying qubits, allowing communication of quantum information over long distances. Self-assembled InAs quantum dots embedded in GaAs constitute an excellent nearly deterministic source of high quality single photons, but the vast majority of sources operate in the 900-950 nm wavelength range, precluding their adoption in a quantum network. Here, we present a quantum frequency conversion scheme for converting single photons from quantum dots to the telecommunication C band, around 1550 nm, achieving 40.8% end-to-end efficiency, while maintaining both high purity and a high degree of indistinguishability during conversion with measured values of $g^{(2)}(0)=2.4\%$ and $V^{\text{corr}}=94.8\%$, respectively.

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Beatrice Da Lio, Carlos Faurby, Xiaoyan Zhou, Ming Lai Chan, Ravitej Uppu, Henri Thyrrestrup, Sven Scholz, Andreas D. Wieck, Arne Ludwig, Peter Lodahl, Leonardo Midolo. 2022-01-07. A Pure and indistinguishable single-photon source at telecommunication wavelength. https://arxiv.org/abs/2201.02465

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