Free-Space Time-Bin Encoded Quantum Key Distribution from Near- to Mid-Infrared Wavelengths

Year: 2026

Authors: De Lazzari C., Gabbrielli T., Bruno N., Cappelli F., Ribezzo D., Biagi N., Corrias N., Borri S., de Cumis M.S., De Natale P., Bacco D., Zavatta A.

Autors Affiliation: QTI Srl, Florence, Italy; CNR Ist Nazl Ottica CNR INO, Florence, Italy; LENS European Lab Nonlinear Spect, Sesto Fiorentino, FI, Italy; Univ Firenze, Dept Phys & Astron, Florence, Italy; Ctr Spaziale G Colombo, ASI Agenzia Spaziale Italiana, Matera, Italy.

Abstract: Quantum technologies play a central role in establishing new ways of quantum-secured communication. This work investigates free-space quantum communication and explores the advantage of implementing quantum key distribution (QKD) with weak coherent states produced by a light source in the mid-infrared (). Time-bin encoded quantum key distribution is simulated, and it is demonstrated 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.

Journal/Review: ADVANCED QUANTUM TECHNOLOGIES

Volume: 9 (4)      Pages from: e00867-1  to: e00867-11

More Information: C.D.L. and T.G. equally contributed to this work. The Authors acknowledge financial support from EU NextGenerationEU Program with the I-PHOQS Infrastructure Integrated infrastructure initiative in Photonic and Quantum Sciences (IR0000016, ID D2B8D520, CUP B53C22001750006); and the project SERICS – SEcurity and RIghts in the CyberSpace (PE00000014). This work was also partially supported by European Commission with Laserlab-Europe Project (G.A. n.871124), MUQUABIS Project Multiscale quantum bio-imaging and spectroscopy (G.A. n.101070546), QUID project Quantum Italy Deployment (G.A. No 101091408), E QUO project European QUantum ecOsystems (G.A. No 101091561); from the Italian ESFRI Roadmap (Extreme Light Infrastructure – ELI Project); from ASI and CNR under the Joint Project Laboratori congiunti ASI-CNR nel settore delle Quantum Technologies (QASINO) (Accordo Attuativo n. 2023-47-HH.0); from the Italian Ministero dell’Universita e della Ricerca (project PRIN-2022KH2KMT QUAQK). A.Z. acknowledges financial support by Consiglio Nazionale delle Ricerche (CNR) with QuONTENT project under the Progetti di Ricerca@CNR program.
KeyWords: free-space communication; mid-infrared; quantum key distribution; time-bin encoding
DOI: 10.1002/qute.202500867