Coexistence of entanglement-based quantum channels with DWDM classical channels over hollow core fibre in a four node quantum communication network
M. J. Clark, Obada Alia, Sima Bahrani +10 more
We experimentally demonstrate the coexistence of three entanglement-based quantum channels with carrier-grade classical optical channels over 11.5 km hollow core nested antiresonant nodeless fibre, in a four user quantum network. A transmission of 800 Gbps is achieved with four classical channels simultaneously with three quantum channels all operating in the C-band with a separation of 1.2 nm, with aggregated coexistence power of -3 dBm. We established quantum key distribution in the four-node full-mesh quantum network with Bell state fidelity of up to 90.0 ± 0.8%. The secret key rate for all the links in the network are passively preserved over 55 hours of experimental time.
arXiv:2508.00072•npj Quantum Information•Nov 19, 2025•4 citations