Engineering light-matter interfaces for quantum networks
The realization of a future quantum Internet relies on processingand storage ofquantum information at local nodes and interconnecting distant nodes using photons (1). Light-matter interfaces constitutebuilding blocksfor such networks:they allow forcoherent control and reversible transfer of quantum information between “stationary” atoms and “flying” photons. Despite impressiveprogress over the pasttwo decades, there are still severalobstacles neededto be overcome for practical realizations. In my talk, I will address these challenges and presentour experimental efforts in view of requirements of quantum networks. Particularly, I will focus on integrated light-matterinterfacesbased on rare-earth ions and show our demonstrations including the storage of photonic entanglementusingthese devices (2-4). Furthermore, I will present a novel approach to develop a broadband spin-photon interface for long-lived storage and manipulation of lightalong with the proof-of-principle implementations in an ensemble of laser-cooled atoms (5) and a Bose-Einstein condensate (6). Finally, I will discuss my research plans towards the realization of large-scale quantum networksand its potential applications,including quantum secure key distribution and distributed quantum computing.