arXiv:quant-ph/0403104 · Japanese Journal of Applied Physics

Single-photon Interference over 150 km Transmission Using Silica-based Integrated-optic Interferometers for Quantum Cryptography

Tadamasa Kimura, Yoshihiro Nambu, T. Hatanaka, Akihisa Tomita, Hideo Kosaka, Kazuo Torii Nakamura

Published Sep 1, 2004• 98 citations

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.

DOI: 10.1143/jjap.43.l1217

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