Pairs of entangled photons are a key ingredient of photonic quantum computers, quantum key distribution systems, and many quantum networking designs. Producing entangled photons on demand generally requires bulky lasers and prolonged alignment procedures – and this limits the commercial viability of these technologies. Now, a team of researchers in Germany and the Netherlands have used a new architecture to combine several integrated photonic technologies into one device. The result is a complete entangled photon source on a chip that is about the size of a one euro coin.
To read more, click here.