Long-Distance Free-Space Distribution of Entangled Photons
19. Jun 2003 — (Science Express, June 19, 2003; Science Vol. 301, pp.621)
by Markus Aspelmeyer, Hannes R. Böhm, Tsewang Gyatso, Thomas Jennewein, Rainer Kaltenbaek, Michael Lindenthal, Gabriel Molina-Terriza, Andreas Poppe, Kevin Resch, Michael Taraba, Rupert Ursin, Philip Walther, Anton Zeilinger
Demonstration of the distribution of quantum entanglement via optical free-space links to independent receivers separated by 600 m and without a line of sight between each other. A Bell inequality between those receivers is violated by more than 4 standard deviations confirming the quality of the entanglement. This outdoor experiment represents a step towards satellite-based distributed quantum entanglement.