Quantum entanglement on photonic chips: a review

Entanglement is one of the most vital properties of quantum mechanical systems, and it forms the backbone of quantum information technologies. Taking advantage of nano/microfabrication and particularly complementary metal-oxide-semiconductor manufacturing technologies, photonic integrated circuits (PICs) have emerged as a versatile platform for the generation, manipulation, and measurement of entangled photonic states. We summarize the recent progress of quantum entanglement on PICs, starting from the generation of nonentangled and entangled biphoton states, to the generation of entangled states of multiple photons, multiple dimensions, and multiple degrees of freedom, as well as their applications for quantum information processing.

Automated summary

Entanglement is a vital property of quantum systems and forms the backbone of quantum information technologies, with photonic integrated circuits playing a key role in generating, manipulating, and measuring entangled photonic states for quantum information processing.