Entanglement swapping allows to establish entanglement between independent particles that never interacted nor share any common past. This feature makes it an integral constituent of quantum repeaters. Here, we demonstrate entanglement swapping with time-synchronized independent sources with a fidelity high enough to violate a Clauser-Horne-Shimony-Holt inequality by more than four standard deviations. The fact that both entangled pairs are created by fully independent, only electronically connected sources ensures that this technique is suitable for future long-distance quantum communication experiments as well as for novel tests on the foundations of quantum physics.
@article{arxiv.0809.3991,
title = {High-fidelity entanglement swapping with fully independent sources},
author = {Rainer Kaltenbaek and Robert Prevedel and Markus Aspelmeyer and Anton Zeilinger},
journal= {arXiv preprint arXiv:0809.3991},
year = {2009}
}
Comments
added technical details and extended introduction and conclusion, slightly modified the abstract, corrected a mistake in the affiliations