Realization of a multi-node quantum network of remote solid-state qubits

Pompili, Matteo; Hermans, Sophie L. N.; Baier, Simon; Beukers, Hans K. C.; Humphreys, Peter C.; Schouten, Raymond N.; Vermeulen, Raymond F. L.; Tiggelman, Marijn J.; Martins, Laura dos Santos; Dirkse, Bas; Wehner, Stephanie; Hanson, Ronald

The distribution of entangled states across the nodes of a future quantum internet will unlock fundamentally new technologies. Here we report on the experimental realization of a three-node entanglement-based quantum network. We combine remote quantum nodes based on diamond communication qubits into a scalable phase-stabilized architecture, supplemented with a robust memory qubit and local quantum logic. In addition, we achieve real-time communication and feed-forward gate operations across the network. We capitalize on the novel capabilities of this network to realize two canonical protocols without post-selection: the distribution of genuine multipartite entangled states across the three nodes and entanglement swapping through an intermediary node. Our work establishes a key platform for exploring, testing and developing multi-node quantum network protocols and a quantum network control stack.