Quantum networks have the potential to unlock significant advancements in secure communications. Such networks require nodes which perform quantum processing on a small register of interconnected qubits with long coherence times. Harvard researchers have developed a nanophotonic device which has advantages over current technologies that make them more suitable for large-scale networks. This innovation makes use of silicon-vacancy color-centers in diamond (SiV) to build a quantum network node with SiV centers coupled to ancillary nuclear spins. This system can achieve high-fidelity, coherent control of multiple long-lived quibits, forming the basis for a network with unconditionally secure communication between distant parties.

This work has been published in Physical Review B.