Three's a charm: NIST detectors reveal entangled photon triplets
From NIST Tech Beat: September 15, 2014
Researchers at the Institute for Quantum Computing at the University of Waterloo in Canada have directly entangled three photons in the most technologically useful state for the first time, thanks in part to superfast, super-efficient single-photon detectors developed by the National Institute of Standards and Technology (NIST).