Entanglement distribution over 300 km of fiber
Takahiro Inagaki, Nobuyuki Matsuda, Osamu Tadanaga, Masaki Asobe, Hiroki Takesue · Optics Express · 2013
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/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.