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arXiv · 1101.1009

Faithful entanglement swapping based on sum-frequency generation

Nicolas Sangouard·Bruno Sanguinetti·Noe Curtz·Nicolas Gisin·Rob Thew·Hugo Zbinden
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Abstract

We show that the entanglement resulting from an entanglement swapping operation performed with spontaneous parametric down-conversion can be made faithful without post-selection using sum-frequency generation. This invites us to revisit the sum-frequency process and from a proof-of-principle experiment, we demonstrate that it provides a realistic solution for non-linear optics at the single-photon level. This opens the way to attractive alternatives to six-photon protocols based on linear optics used e.g. for the heralded creation of maximally entangled pairs or for the implementation of device-independent quantum key distribution.

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Nicolas Sangouard, Bruno Sanguinetti, Noe Curtz, Nicolas Gisin, Rob Thew, Hugo Zbinden. 2011-03-23. Faithful entanglement swapping based on sum-frequency generation. https://doi.org/10.1103/physrevlett.106.120403

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