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arXiv · 2507.11175

Versatile Wavelength-Division Multiplexed Quantum Key Distribution Network Operating Simultaneously in the O and C Bands

Davide Scalcon·Matteo Padovan·Paolo Villoresi·Giuseppe Vallone·Marco Avesani
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Abstract

Ongoing technological progress is accelerating the commercial and global-scale deployment of Quantum Key Distribution (QKD). Its ability to enable unconditionally secure communication is expected to be a key feature of future telecommunication networks, and practical demonstrations of QKD network implementations in real-world environments are crucial for ensuring reliable adoption. In this work, we demonstrate a four-node photonic QKD network that employs versatile and cost-effective wavelength-division multiplexing across three transmitters in the O and C bands to simultaneously distribute quantum-secure keys among all nodes. Specifically, the broadband central receiver node shares all optical and electronic decoding components, except for the single-photon detectors, across the three QKD links, significantly reducing system costs and enhancing compactness.

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Davide Scalcon, Matteo Padovan, Paolo Villoresi, Giuseppe Vallone, Marco Avesani. 2025-07-15. Versatile Wavelength-Division Multiplexed Quantum Key Distribution Network Operating Simultaneously in the O and C Bands. https://doi.org/10.1364/opticaq.579856

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