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arXiv · 1807.10690

Long-term transmission of entangled photons from single quantum dot over deployed fiber

Zi-Heng Xiang·Jan Huwer·R. Mark Stevenson·Joanna Skiba-Szymanska·Martin B. Ward·Ian Farrer·David A. Ritchie·Andrew J. Shields
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Abstract

Non-classical light sources based on a single quantum emitter are considered as core technology for multiple quantum network architectures. A large variety of sources has been developed, but the generated photons remained far from being utilized in established standard fiber networks. Here, we report a week-long transmission of polarization-entangled photons from a single InAs/GaAs quantum dot over a metropolitan network fiber. The emitted photons are in the telecommunication O-band, favored for fiber optical communication. We employ a polarization stabilization system overcoming changes of birefringence introduced by 18.23km of installed fiber. Stable transmission of polarization-encoded entanglement with a high fidelity of 91% is achieved, facilitating the operation of sub-Poissonian quantum light sources over existing fiber networks.

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Zi-Heng Xiang, Jan Huwer, R. Mark Stevenson, Joanna Skiba-Szymanska, Martin B. Ward, Ian Farrer, David A. Ritchie, Andrew J. Shields. 2018-07-27. Long-term transmission of entangled photons from single quantum dot over deployed fiber. https://doi.org/10.1038/s41598-019-40912-z

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