Distributing entanglement with separable states

Phys Rev Lett. 2013 Dec 6;111(23):230506. doi: 10.1103/PhysRevLett.111.230506. Epub 2013 Dec 4.

Abstract

We experimentally demonstrate a protocol for entanglement distribution by a separable quantum system. In our experiment, two spatially separated modes of an electromagnetic field get entangled by local operations, classical communication, and transmission of a correlated but separable mode between them. This highlights the utility of quantum correlations beyond entanglement for the establishment of a fundamental quantum information resource and verifies that its distribution by a dual classical and separable quantum communication is possible.