Free-space quantum links have clear practical advantages which are unaccessible with fiber-based optical channels — establishing satellite-mediated quantum links, communications through hardly accessible regions, and communications with moving objects. We consider the effect of the atmospheric turbulence on properties such as quadrature squeezing, entanglement, Bell nonlocality, and nonclassical statistics of photocounts, which are resources for quantum communications. Depending on the characteristics of the given channels, we study the efficiency of different techniques, which enable to preserve these quantum features post-, pre-selection, and adaptive methods. Furthermore, we show that copropagation of nonclassically-correlated modes, which is used in some communication scenarios, has clear advantages in free-space links.

Date Published: 18 September 2018
PDF: 16 pages
Proc. SPIE 10771, Quantum Communications and Quantum Imaging XVI, 107710Z (18 September 2018); doi: 10.1117/12.2319475

Published in SPIE Proceedings Vol. 10771:
Quantum Communications and Quantum Imaging XVI
Ronald E. Meyers; Yanhua Shih; Keith S. Deacon, Editor(s)