In the latest paper3, which was submitted to the arXiv preprint repository on 24 August and has not yet been peer reviewed, a team led by Ronald Hanson of Delft University of Technology reports the first Bell experiment that closes both the detection and the communication loopholes. The team used a cunning technique called entanglement swapping to combine the benefits of using both light and matter. The researchers started with two unentangled electrons sitting in diamond crystals held in different labs on the Delft campus, 1.3 kilometres apart. Each electron was individually entangled with a photon, and both of those photons were then zipped to a third location
. There, the two photons were entangled with each other — and this caused both their partner electrons to become entangled, too.