PT Journal AU Kok, P TI Quantum optics: Entangled photons report for duty SO Nature Photonics JI Nat. Photon. PY 2010 BP 504 EP 505 VL 4 IS 8 DE fromIPMRAS AB Entangled photons are a key ingredient in optical quantum technologies, but researchers have so far been unable to produce a single pair of entangled photons. Now, two groups from China and Austria independently report just that, with a technique that avoids the need to infer entanglement from detection signatures. ER