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Single-photon interference experiment over 100 km for quantum cryptography system using a balanced gated-mode photon detector

Hideo Kosaka·Akihisa Tomita·Yoshihiro Nambu·Tadamasa Kimura·Kazuo Nakamura
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Abstract

We demonstrate single-photon interference over 100 km using a balanced gated-mode photon detector and a plug & play system for quantum key distribution. The visibility with 0.1 photon/pulse was more than 80% after 100 km transmission. This corresponds to the fidelity of a quantum cryptography system of more than 90% and a QBER of less than 10%, satisfying the security criteria.

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Hideo Kosaka, Akihisa Tomita, Yoshihiro Nambu, Tadamasa Kimura, Kazuo Nakamura. 2003-06-10. Single-photon interference experiment over 100 km for quantum cryptography system using a balanced gated-mode photon detector. https://arxiv.org/abs/quant-ph/0306066

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