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Single-photon interference over 150-km transmission using silica-based integrated-optic interferometers for quantum cryptography

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

We have demonstrated single-photon interference over 150 km using time-division interferometers for quantum cryptography, which were composed of two integrated-optic asymmetric Mach-Zehnder interferometers, and balanced gated-mode photon detectors. The observed fringe visibility was more than 80% after 150-km transmission.

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Tadamasa Kimura, Yoshihiro Nambu, Takaaki Hatanaka, Akihisa Tomita, Hideo Kosaka, Kazuo Nakamura. 2004-09-07. Single-photon interference over 150-km transmission using silica-based integrated-optic interferometers for quantum cryptography. https://doi.org/10.1143/jjap.43.l1217

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