Analysis of satellite-to-ground quantum key distribution with adaptive optics

Tue, 20 Feb 2024 00:00:00 +0000

Future quantum communication infrastructures will rely on both terrestrial and space-based links integrating high-performance optical systems engineered for this purpose. In space-based downlinks in particular, the loss budget and the variations in the signal propagation due to atmospheric turbulence effects impose a careful optimization of the coupling of light in single-mode fibers required for interfacing with the receiving stations and the ground networks. In this work, we perform a comprehensive study of the role of adaptive optics (AO) in this optimization, focusing on realistic baseline configurations of prepare-and-measure quantum key distribution (QKD), with both discrete and continuous-variable encoding, and including finite-size effects. Our analysis uses existing experimental turbulence datasets at both day and night time to model the coupled signal statistics following a wavefront distortion correction with AO, and allows us to estimate the secret key rate for a range of critical parameters, such as turbulence strength, satellite altitude and ground telescope diameter. The results we derive illustrate the interest of adopting advanced AO techniques in several practical configurations.

Improvement of satellite-to-ground QKD secret key rate with adaptive optics

Sun, 05 Mar 2023 00:00:00 +0000

We demonstrate the gain brought by adaptive optics for space-ground QKD links. Refined modeling of turbulence, adaptive optics and QKD, including finite-size effects, shows improvement by several orders of magnitude of the secret key rate.

Aurélie Montmerle-Bonnefois | LIP6 - Équipe QI

Analysis of satellite-to-ground quantum key distribution with adaptive optics

Improvement of satellite-to-ground QKD secret key rate with adaptive optics