Two-node Remote Quantum Network using Silicon-Vacancy Centers in a Diamond Nanophotonic System (Part 1)

The realization of a long-range quantum network will connect future quantum computers and could enable provably secure communications. Here, we present the silicon-vacancy (SiV) center in diamond as a promising solid-state quantum network platform capable of deployment in a practical setting. In the first of this two-part talk, we show that the ²⁹Si-isotope SiV is highly suited as an integrated two-qubit register with the ability for universal single- and two-qubit gate operations, high-fidelity readout, and possesses a long-lived memory in the nuclear spin. With the choice of a highly strained SiV, we additionally sustain spin coherence properties above dilution refrigerator temperatures. Quantum network nodes also require light-matter interfaces for remote entanglement, and the SiV is optically accessible with excellent in-fiber collection efficiency through implantation in high-cooperativity nanophotonic cavities. We demonstrate efficient heralded spin-photon gates to create electron-photon and nuclear-photon Bell states with integrated error detection – both key components towards the implementation of entanglement distribution across two physically separated nodes, which will be described in the second part of this talk.