First Demonstration of 25{\lambda} x 10 Gb/s C+L Band Classical / DV-QKD Co-Existence Over Single Bidirectional Fiber Link

Florian Honz; Florian Prawits; Obada Alia; Hesham Sakr; Thomas Bradley; Cong Zhang; Radan Slavík; Francesco Poletti; George Kanellos; Reza Nejabati; Philip Walther; Dimitra Simeonidou; Hannes Hübel; Bernhard Schrenk

arXiv · 2403.13503

First Demonstration of 25{\lambda} x 10 Gb/s C+L Band Classical / DV-QKD Co-Existence Over Single Bidirectional Fiber Link

Florian Honz·Florian Prawits·Obada Alia·Hesham Sakr·Thomas Bradley·Cong Zhang·Radan Slavík·Francesco Poletti·George Kanellos·Reza Nejabati·Philip Walther·Dimitra Simeonidou·Hannes Hübel·Bernhard Schrenk

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Abstract

As quantum key distribution has reached the maturity level for practical deployment, questions about the co-integration with existing classical communication systems are of utmost importance. To this end we demonstrate how the co-propagation of classical and quantum signals can benefit from the development of novel hollow-core fibers. We demonstrate a secure key rate of 330 bit/s for a quantum channel at 1538 nm in the presence of 25 x 10 Gb/s classical channels, transmitted at an aggregated launch power of 12 dBm, spanning over the C+L-band in the same hollow-core fiber link. Furthermore, we show the co-integration of the classical key-distillation channel onto this fiber link, turning it into a bidirectional fiber link and thereby mitigating the need for multiple fibers. We believe this to be an important step towards the deployment and integration of hollow-core fibers together with DV-QKD for the inherently secure telecom network of the future.

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Florian Honz, Florian Prawits, Obada Alia, Hesham Sakr, Thomas Bradley, Cong Zhang, Radan Slavík, Francesco Poletti, George Kanellos, Reza Nejabati, Philip Walther, Dimitra Simeonidou, Hannes Hübel, Bernhard Schrenk. 2024-03-20. First Demonstration of 25{\lambda} x 10 Gb/s C+L Band Classical / DV-QKD Co-Existence Over Single Bidirectional Fiber Link. https://arxiv.org/abs/2403.13503

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