September 2004:

Photonic crystal based entangled photon sources appear as a research highlight in Nature Materials 3, 582 (2004). The work would have been impossible without the important contributions of Dirk Bouwmeester and especially William Irvine.
The original article "Non-linear photonic crystals as a source of entangled photons" by M.J.A. de Dood, W.T.M. Irvine and D. Bouwmeester, Phys. Rev. Lett. 93 40504 (2004) is available in PDF Format (116 kB)