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arXiv · 1006.4585

Coherent frequency-down-conversion interface for quantum repeaters

Noé Curtz·Rob Thew·Christoph Simon·Nicolas Gisin·Hugo Zbinden
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Abstract

We report a coherence-preserving photon frequency down-conversion experiment based on difference-frequency generation in a periodically poled Lithium niobate waveguide, at the single-photon level. The coherence of the process has been demonstrated by measuring the phase coherence of pseudo single-photon time-bin qubits after frequency conversion with an interference visibility of > 96 %. This interface could be of interest for quantum repeater based hybrid networks.

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Noé Curtz, Rob Thew, Christoph Simon, Nicolas Gisin, Hugo Zbinden. 2010-06-23. Coherent frequency-down-conversion interface for quantum repeaters. https://doi.org/10.1364/oe.18.022099

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