Multiplexed telecommunication-band quantum networking with atom arrays in optical cavities

Abstract

The realization of a quantum network node of matter-based qubits compatible with telecommunication-band operation and large-scale quantum information processing is an outstanding challenge that has limited the potential of elementary quantum networks. We propose a platform for interfacing quantum processors comprising neutral atom arrays with telecommunication-band photons in a multiplexed network architecture. The use of a large atom array instead of a single atom mitigates the deleterious effects of two-way communication and improves the entanglement rate between two nodes by nearly two orders of magnitude. Furthermore, this system simultaneously provides the ability to perform high-fidelity deterministic gates and readout within each node, opening the door to quantum repeater and purification protocols to enhance the length and fidelity of the network, respectively. Using intermediate nodes as quantum repeaters, we demonstrate the feasibility of entanglement distribution over $\ensuremath{\approx}1500\phantom{\rule{0.28em}{0ex}}\text{km}$ based on realistic assumptions, providing a blueprint for a transcontinental network. Finally, we demonstrate that our platform can distribute $\ensuremath{\gtrsim}25$ Bell pairs over metropolitan distances, which could serve as the backbone of a distributed fault-tolerant quantum computer.