Experimental Entanglement Distribution by Separable States
Christina E. Vollmer, Daniela Schulze, T. Eberle, Vitus Händchen, Jaromı́r Fiurášek, Roman Schnabel · Physical Review Letters · 2013
Distribution of entanglement between macroscopically separated parties is crucial for future quantum information networks. Surprisingly, it has been theoretically shown that two distant systems can be entangled by sending a third system that is not entangled with either of them. Here, we experimentally distribute entanglement and successfully prove that our transmitted light beam is indeed not entangled with the parties' local systems. Our work demonstrates an unexpected variant of entanglement distribution and improves the understanding necessary to engineer multipartite quantum networks.