Quantum information transfer using photons

Recent advances in quantum information transfer by photons are reviewed. The theoretical framework for information transfer between nodes of a quantum network is described, and several key experiments for remote atom–atom entanglement mediated by light are illustrated. The prospects for hybrid systems currently in development are also discussed. Optical communication channels have redefined the scope and applications of classical computing; similarly, photonic transfer of quantum information promises to open new horizons for quantum computing. The implementation of light–matter interfaces that preserve quantum information is technologically challenging, but key building blocks for such devices have recently been demonstrated by several research groups. Here, we outline the theoretical framework for information transfer between the nodes of a quantum network, review the current experimental state of the art and discuss the prospects for hybrid systems currently in development.