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Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)

Quantum key distribution over a 60-dB channel loss using SSPD with ultralow dark count rate

Hiroyuki Shibata, Toshimori Honjo, Kaoru Shimizu

Published Jun 1, 2013• 1 citation
Publisher

Abstract

We present the first quantum key distribution (QKD) experiment over 60 dB channel loss, which is equivalent to 300 km of fiber. We use the differential phase shift QKD protocol and ultra-low dark count SSPDs.
DOI
10.1109/cleopr.2013.6600637

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Quantum key distribution (QKD) leverages quantum mechanics to establish secure communication channels. Recent advancements in differential phase shift QKD (DPS-QKD) have enabled secure key distribution over 200 km with a 42 dB channel loss, facilitated by technologies like superconducting single-photon detectors (SSPDs) and high-performing nanowires. This paper delves into the mathematical modeling of QKD protocols, experimental achievements, and their implications for long-distance secure communication. Theoretical formulations for secure key rates, channel losses, and error probabilities are presented, alongside a review of relevant works that laid the foundation for modern QKD systems.
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