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arXiv · 1910.06506

Two-color Bell states heralded via entanglement swapping

Sofiane Merkouche·Valérian Thiel·Alex O. C. Davis·Brian J. Smith
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Abstract

We report on an experiment demonstrating entanglement swapping of time-frequency entangled photons. We perform a frequency-resolved Bell-state measurement on the idler photons from two independent entangled photon pairs, which projects the signal photons onto a two-color Bell state. We verify entanglement in this heralded state using two-photon interference and observing quantum beating without the use of filters, indicating the presence of two-color entanglement. Our method could lend itself to use as a highly-tunable source of frequency-bin entangled single photons.

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Sofiane Merkouche, Valérian Thiel, Alex O. C. Davis, Brian J. Smith. 2019-10-15. Two-color Bell states heralded via entanglement swapping. https://arxiv.org/abs/1910.06506

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