Entanglement and quantum repeaters

For years, physicists have managed to entangle elementary particles of light. Recently, Nicolas Gisin's team successfully demonstrated that entanglement can also link two macroscopic crystals that are each visible to the naked eye. This constitutes an important step towards the realization of quantum repeaters. Their work has been published in the latest issue of Nature Photonics.

I. Usmani et al., Nature Photonics 6, 234–237 (2012)