Entanglement over global distances via quantum repeaters with satellite   links
  We study entanglement creation over global distances based on a quantum repeater architecture that uses low-earth orbit satellites equipped with entangled photon sources, as well as ground stations equipped with quantum non-demolition detectors and quantum memories. We show that this approach allows entanglement creation at viable rates over distances that are inaccessible via direct transmission through optical fibers or even from very distant satellites. 
K. Boone, J.-P. Bourgoin, E. Meyer-Scott, K. Heshami, T. Jennewein, C.   Simon
quant-ph