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Optical Fiber Communication Conference

Implementing QKD over Multi-Fiber Ribbon Cables: How Dark is the “Dark Fiber”?

Florian Honz, Vana Pezelj, Theodor Strobl, Florian Kutschera, Valeria Saggio, P. Walther, Hannes Hübel, Bernhard Schrenk

Published Jan 1, 2026• 0 citations

Abstract

We identify inter-lane crosstalk as main cause for QKD degradation in 1×12 bend-loss insensitive fiber ribbon cables. Despite allocating QKD to unused fiber lanes, neighboring classical signals can lead to total saturation of single-photon detectors.

DOI: 10.1364/ofc.2026.w3k.1

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