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arXiv · 1310.5473

Entanglement distribution over 300 km of fiber

Takahiro Inagaki·Nobuyuki Matsuda·Osamu Tadanaga·Masaki Asobe·Hiroki Takesue
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Abstract

We report the distribution of time bin entangled photon pairs over 300 km of optical fiber. We realized this by using a high speed and high signal to noise ratio entanglement generation and evaluation setup that consists of periodically poled lithium niobate waveguides and superconducting single photon detectors. The observed two-photon interference fringes exhibited a visibility of 84 %. We confirmed the violation of Bell's inequality by 2.9 standard deviations.

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Takahiro Inagaki, Nobuyuki Matsuda, Osamu Tadanaga, Masaki Asobe, Hiroki Takesue. 2013-10-21. Entanglement distribution over 300 km of fiber. https://doi.org/10.1364/oe.21.023241

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