Long-Distance Free-Space Distribution of Quantum Entanglement

  title={Long-Distance Free-Space Distribution of Quantum Entanglement},
  author={Markus Aspelmeyer and Hannes R. B{\"o}hm and Tsewang Gyatso and Thomas Jennewein and Rainer Kaltenbaek and Michael Lindenthal and Gabriel Molina-Terriza and Andreas Poppe and Kevin J. Resch and Michael Taraba and Rupert Ursin and Philip Walther and Anton Zeilinger},
  pages={621 - 623}
We demonstrate the distribution of quantum entanglement via optical free-space links to independent receivers separated by 600 m, with no line of sight between each other. A Bell inequality between those receivers is violated by more than four standard deviations, confirming the quality of the entanglement. This outdoor experiment represents a step toward satellite-based distributed quantum entanglement. 
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