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arXiv · 2508.13008

Free-space time-bin encoded quantum key distribution from near- to mid-infrared wavelengths

Claudia De Lazzari·Tecla Gabbrielli·Natalia Bruno·Francesco Cappelli·Domenico Ribezzo·Nicola Biagi·Nicola Corrias·Simone Borri·Mario Siciliani de Cumis·Paolo De Natale·Davide Bacco·Alessandro Zavatta
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Abstract

Quantum technologies play a central role in establishing new ways of quantum-secured communication. We investigate Free-Space Quantum Communication and explore the advantage of implementing Quantum Key Distribution (QKD) with weak coherent states produced by a light source in the Mid-Infrared (>3$\mu$m). We simulate time-bin encoded quantum key distribution and demonstrate that a free-space QKD link operating in the Mid-infrared outperforms configurations based on conventional near-infrared wavelengths under various weather scenarios, with a particular significance in adverse meteorological conditions.

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Claudia De Lazzari, Tecla Gabbrielli, Natalia Bruno, Francesco Cappelli, Domenico Ribezzo, Nicola Biagi, Nicola Corrias, Simone Borri, Mario Siciliani de Cumis, Paolo De Natale, Davide Bacco, Alessandro Zavatta. 2025-08-18. Free-space time-bin encoded quantum key distribution from near- to mid-infrared wavelengths. https://doi.org/10.1002/qute.202500867

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