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arXiv · 2004.09465

Heralded distribution of single-photon path entanglement

Patrik Caspar·Ephanielle Verbanis·Enky Oudot·Nicolas Maring·Farid Samara·Misael Caloz·Matthieu Perrenoud·Pavel Sekatski·Anthony Martin·Nicolas Sangouard·Hugo Zbinden·Rob Thew
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Abstract

We report the experimental realization of heralded distribution of single-photon path entanglement at telecommunication wavelengths in a repeater-like architecture. The entanglement is established upon detection of a single photon, originating from one of two spontaneous parametric down conversion photon pair sources, after erasing the photon's which-path information. In order to certify the entanglement, we use an entanglement witness which does not rely on post-selection. We herald entanglement between two locations, separated by a total distance of 2 km of optical fiber, at a rate of 1.6 kHz. This work paves the way towards high-rate and practical quantum repeater architectures.

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Patrik Caspar, Ephanielle Verbanis, Enky Oudot, Nicolas Maring, Farid Samara, Misael Caloz, Matthieu Perrenoud, Pavel Sekatski, Anthony Martin, Nicolas Sangouard, Hugo Zbinden, Rob Thew. 2020-04-20. Heralded distribution of single-photon path entanglement. https://doi.org/10.1103/physrevlett.125.110506

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