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Long-distance distribution of time-bin entanglement generated in a cooled fiber

Hiroki Takesue
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Abstract

This paper reports the first demonstration of the generation and distribution of entangled photon pairs in the 1.5-um band using spontaneous four-wave mixing in a cooled fiber. Noise photons induced by spontaneous Raman scattering were suppressed by cooling a dispersion shifted fiber with liquid nitrogen, which resulted in a significant improvement in the visibility of two-photon interference. By using this scheme, time-bin entangled qubits were successfully distributed over 60 km of optical fiber with a visibility of 76%, which was obtained without removing accidental coincidences.

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Hiroki Takesue. 2005-12-21. Long-distance distribution of time-bin entanglement generated in a cooled fiber. https://doi.org/10.1364/oe.14.003453

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