University of Waterloo

Published purpose

The Project aims to overcome fundamental limits in quantum communication and establish Canada as a leader in quantum networking. Today’s systems are restricted by photon loss in fibers, where the so-called PLOB bound sets the ultimate limit for secure direct communication. The project team’s approach introduces a multimode, cavity QED-based repeater architecture with chiral light-matter coupling. This enables highly efficient entanglement distribution, directional photon interactions, and multiplexed quantum memory. These advances are expected to surpass the PLOB bound by 3–5 dB over metropolitan fiber networks—representing the first experimental violation of this theoretical limit. Unlike incremental progress pursued elsewhere, the Project uniquely integrates secure quantum communication with quantumenhanced sensing and metrology within NRC’s testbed as a general quantum networking infrastructure. Potential applications include entanglement-assisted interferometry for astronomy and defense, quantum key distribution, and fault-tolerant distributed computing. By creating deployment-ready, modular infrastructure, the project directly supports Canada’s National Quantum Strategy and positions the country at the forefront of global quantum technology