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arXiv · 1904.00164

Pulsed Sagnac source of polarization-entangled photon pairs in telecommunication band

Heonoh Kim·Osung Kwon·Han Seb Moon
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Abstract

We report a source of polarization-entangled photon pairs in the 1550-nm telecommunication band, which is based on non-collinear spontaneous parametric down-conversion in a periodically poled lithium niobate crystal pumped by picosecond pulses. This source is realized utilizing a polarization-based Sagnac interferometer employing a type-0 non-collinear quasi-phase-matching configuration. Polarization entanglement is verified through measurement of the polarization-correlation interference fringes with visibility >96% and by testing the experimental violation of the Clauser-Horne-Shimony-Holt (CHSH) form of Bell inequality. The CHSH-Bell parameter S is found to be 2.72 \pm 0.04, with 18 standard deviations from the statistical uncertainty.

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Heonoh Kim, Osung Kwon, Han Seb Moon. 2019-03-30. Pulsed Sagnac source of polarization-entangled photon pairs in telecommunication band. https://arxiv.org/abs/1904.00164

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