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arXiv · 0805.2193

Ultra fast quantum key distribution over a 97 km installed telecom fiber with wavelength-division multiplexing clock synchronization

Akihiro Tanaka·Mikio Fujiwara·Sae Woo Nam·Yoshihiro Nambu·Seigo Takahashi·Wakako Maeda·Ken-ichiro Yoshino·Shigehito Miki·Burm Baek·Zhen Wang·Akio Tajima·Masahide Sasaki·Akihisa Tomita
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Abstract

We demonstrated ultra fast BB84 quantum key distribution (QKD) transmission at 625 MHz clock rate through a 97 km field-installed fiber using practical clock synchronization based on wavelength-division multiplexing (WDM). We succeeded in over-one-hour stable key generation at a high sifted key rate of 2.4 kbps and a low quantum bit error rate (QBER) of 2.9%. The asymptotic secure key rate was estimated to be 0.78-0.82 kbps from the transmission data with the decoy method of average photon numbers 0, 0.15, and 0.4 photons/pulse.

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Akihiro Tanaka, Mikio Fujiwara, Sae Woo Nam, Yoshihiro Nambu, Seigo Takahashi, Wakako Maeda, Ken-ichiro Yoshino, Shigehito Miki, Burm Baek, Zhen Wang, Akio Tajima, Masahide Sasaki, Akihisa Tomita. 2008-06-23. Ultra fast quantum key distribution over a 97 km installed telecom fiber with wavelength-division multiplexing clock synchronization. https://doi.org/10.1364/oe.16.011354

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