CNR-INO, QTI and the Italian Space Agency Simulate Mid-Infrared Free-Space Quantum Key Distribution in Advanced Quantum Technologies, October 2026: 10 km Through Fog Against 7.5 km at 1,550 nm, TRL 2

On October 14, 2026, the Italian Space Agency announced a CNR-INO, QTI and ASI study in Advanced Quantum Technologies that simulates free-space quantum key distribution at a mid-infrared wavelength near 4 micrometers. In fog of 1 kilometer visibility the simulated mid-infrared link holds a secure key to 10 kilometers where a telecom-wavelength link stops at 7.5, and it works in daylight because solar background is suppressed above 3 micrometers. The posture is dual-use and the readiness is TRL 2: the study assumes a mid-infrared single-photon detector sixteen times more efficient than today's realistic devices, and no hardware link has been built, which is what still separates a fog-tolerant quantum link from a program office.