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arXiv · 2006.07745

Adaptive-optics-enabled quantum communication: A technique for daytime space-to-Earth links

Abstract

Previous demonstrations of free-space quantum communication in daylight have been touted as significant for the development of global-scale quantum networks. Until now, no one has carefully tuned their atmospheric channel to reproduce the daytime sky radiance and slant-path turbulence conditions as they exist between space and Earth. In this article we report a quantum communication field experiment under conditions representative of daytime downlinks from space. Higher-order adaptive optics increased quantum channel efficiencies far beyond those possible with tip/tilt correction alone while spatial filtering at the diffraction limit rejected optical noise without the need for an ultra-narrow spectral filter. High signal-to-noise probabilities and low quantum-bit-error rates were demonstrated over a wide range of channel radiances and turbulence conditions associated with slant-path propagation in daytime. The benefits to satellite-based quantum key distribution are quantified and discussed.

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BibTeXRIS

Mark T. Gruneisen, Mark L. Eickhoff, Scott C. Newey, Kurt E. Stoltenberg, Jeffery F. Morris, Michael Bareian, Mark A. Harris, Denis W. Oesch, Michael D. Oliker, Michael B. Flanagan, Brian T. Kay, Jonathan D. Schiller, R. Nicholas Lanning. 2021-06-10. Adaptive-optics-enabled quantum communication: A technique for daytime space-to-Earth links. https://doi.org/10.1103/physrevapplied.16.014067

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