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Long distance decoy state quantum key distribution in optical fiber

Danna Rosenberg·Jim W. Harrington·Patrick R. Rice·Philip A. Hiskett·Charles G. Peterson·Richard J. Hughes·Adriana E. Lita·Sae Woo Nam·Jane E. Nordholt
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Abstract

The theoretical existence of photon-number-splitting attacks creates a security loophole for most quantum key distribution (QKD) demonstrations that use a highly attenuated laser source. Using ultra-low-noise, high-efficiency transition-edge sensor photodetectors, we have implemented the first version of a decoy-state protocol that incorporates finite statistics without the use of Gaussian approximations in a one-way QKD system, enabling the creation of secure keys immune to photon-number-splitting attacks and highly resistant to Trojan horse attacks over 107 km of optical fiber.

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Danna Rosenberg, Jim W. Harrington, Patrick R. Rice, Philip A. Hiskett, Charles G. Peterson, Richard J. Hughes, Adriana E. Lita, Sae Woo Nam, Jane E. Nordholt. 2007-05-02. Long distance decoy state quantum key distribution in optical fiber. https://doi.org/10.1103/physrevlett.98.010503

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