Entanglement Distribution in Multi-Platform Buffered-Router-Assisted Frequency-Multiplexed Automated Repeater Chains

TL;DR

This paper proposes a quantum network architecture utilizing quantum routers and spectrally-multiplexed repeaters with buffers, enhancing entanglement distribution rates across complex topologies for future global quantum communication.

Contribution

It introduces a novel multi-platform quantum network design with buffered quantum repeaters and frequency multiplexing, improving entanglement distribution efficiency in complex topologies.

Findings

Buffered quantum repeaters increase entanglement rates.

The architecture is compatible with complex network topologies.

Results indicate feasibility with near-term technology parameters.

Abstract

Realization of a globe-spanning quantum network is a current worldwide goal, where near and long term implementations will benefit from connectivity between platforms optimized for specific tasks. Towards this goal, a quantum network architecture is herewith proposed whereby quantum processing devices based on NV$^-$ colour centers act as quantum routers and, between which, long-distance entanglement distribution is enabled by spectrally-multiplexed quantum repeaters based on absorptive quantum memories in rare-earth ion-doped crystals and imperfect entangled photon-pair sources. The inclusion of a quantum buffer structure between repeaters and routers is shown to, albeit the increased complexity, improve the achievable entanglement distribution rates in the network. Although the expected rate and fidelity results are presented for a simple linear network (point-to-point), complex topologies are compatible with the proposed architecture through the inclusion of an extra layer of temporal multiplexing in the quantum router's operation. Figures of merit are extracted based on parameters found in the literature for near-term scenarios and attest the availability of the proposed buffered-router-assisted frequency-multiplexed automated repeater chain network.