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arXiv · 2508.00072

Coexistence of Entanglement-based Quantum Channels with DWDM Classical Channels over Hollow Core Fibre in a Four Node Quantum Communication Network

Marcus J Clark·Obada Alia·Sima Bahrani·Gregory T Jasion·Hesham Sakr·Periklis Petropoulos·Francesco Poletti·George T Kanellos·John Rarity·Reza Nejabati·Siddarth K Joshi·Rui Wang·Dimitra Simeonidou
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Abstract

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 $90.0\pm0.8$%. The secret key rate for all the links in the network are passively preserved over $55$hours of experimental time.

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Marcus J Clark, Obada Alia, Sima Bahrani, Gregory T Jasion, Hesham Sakr, Periklis Petropoulos, Francesco Poletti, George T Kanellos, John Rarity, Reza Nejabati, Siddarth K Joshi, Rui Wang, Dimitra Simeonidou. 2025-07-31. Coexistence of Entanglement-based Quantum Channels with DWDM Classical Channels over Hollow Core Fibre in a Four Node Quantum Communication Network. https://doi.org/10.1038/s41534-025-01125-7

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