Quantum Communication over Atmospheric Channels: A Framework for Optimizing Wavelength and Filtering

This is the authors' abstract. We don't add key points for this paper.

The wavelength dependence of the daytime performance of free-space quantum channels is crucial to global-scale quantum networking, but has been relatively unexplored, due to a lack of expertise in atmospheric physics among quantum optics researchers. This study makes progress by simulating quantum key distribution at different wavelengths, under daytime spectral radiance and atmospheric turbulence. Even in the face of multiple unfavorable factors, it is found that shorter wavelengths can nonetheless outperform longer ones. The framework and insights of this study are expected to have strong impact, and to serve as stepping stones for analyzing more complex quantum networking protocols.