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On the distribution of 1550-nm photon pairs efficiently generated using a periodically poled lithium niobate waveguide

Shigehiko Mori·Jonas Soderholm·Naoto Namekata·Shuichiro Inoue
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Abstract

We report on the generation of photon pairs in the 1550-nm band suitable for long-distance fiber-optic quantum key distribution. The photon pairs were generated in a periodically poled lithium niobate waveguide with a high conversion-efficiency. Using a pulsed semiconductor laser with a pulse rate of 800 kHz and a maximum average pump power of 50 muW, we obtained a coincidence rate of 600 s^-1. Our measurements are in agreement with a Poissonian photon-pair distribution, as is expected from a comparison of the coherence time of the pump and of the detected photons. An average of 0.9 photon pairs per pulse was obtained.

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Shigehiko Mori, Jonas Soderholm, Naoto Namekata, Shuichiro Inoue. 2005-09-27. On the distribution of 1550-nm photon pairs efficiently generated using a periodically poled lithium niobate waveguide. https://doi.org/10.1016/j.optcom.2006.02.010

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