Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Optical Fiber Communication Conference

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

Obada Alia, M. J. Clark, Sima Bahrani, R. Wang, Gregory T. Jasion, Hesham Sakr, J. R. Hayes, Periklis Petropoulos, Francesco Poletti, George Theodore Kanellos, John Rarity, Reza Nejabati, Siddarth Koduru Joshi, D. Simeonidou

Published Jan 1, 2025• 1 citation
Publisher

Abstract

We experimentally demonstrated quantum key distribution with average quantum bit error rate of 5.28 % utilising entanglement-based quantum channels coexisting with 800 Gbps classical traffic all operating in the C-band over 11.5 km hollow core fiber in a three-node quantum network.
DOI
10.1364/ofc.2025.tu3d.1

Related papers

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

Experimental Coexistence of Quantum Key Distribution and L-band Classical Communication over Hollow-core Fiber

Weiwen Kong, Tianqi Dou, Yuheng Xie +7 more

We experimentally demonstrate the coexistence of L-band classical communications and QKD over 101.6 km hollow-core fiber, with a classical capacity of 13.6 Tbps and a secure key rate maintained above 8 kbps.

Asia Communications and Photonics Conference•Nov 5, 2025•0 citations

Experimental Demonstration of $47 \times 800 \text{Gbps}$ Classical Communication and QKD Coexistence Over 101.6 Km HCF

Tianqi Dou, Weiwen Kong, Lei Zhang +10 more

We experimentally demonstrate 37.6 Tbps ($47 \times 800 \text{Gbps}$) classical optical communication and quantum key distribution coexisting over a 101.6 km hollow-core fiber, achieving a record capacity and distance to the best of our knowledge. Sustained secure key rate can be maintained at around 5 kbps. ©2025 The Author(s)

European Conference on Optical Communication•Sep 28, 2025•0 citations

Experimental coexistence of quantum key distribution and high-power classical communication over 101.6 km hollow-core fiber

Weiwen Kong, Tianqi Dou, Lei Zhang +8 more

The integration of quantum key distribution (QKD) with classical optical networks has emerged as a pivotal strategy for building secure communication infrastructures. However, achieving their coexistence in silica-core fibers faces inherent limitations due to nonlinear interference, particularly under high classical signal power. In this paper, we experimentally demonstrate the coexistence of classical optical transport networks and QKD over 101.6 km of hollow-core fiber (HCF) with classical power exceeding 20 dBm for the first time to the best of our knowledge. Through systematic theoretical analysis, we characterize HCF’s transmission loss and nonlinear noise generation mechanisms, revealing its unique compatibility with high-power classical–quantum coexistence compared to conventional fibers. To address spectral interference from HCF’s absorption peaks and nonlinear effects, we propose a spectrally optimized multi-stage allocation (SOMA) scheme that coordinates low-loss channel selection and noise suppression. Experimental validation shows that, under the SOMA scheme, coexisting classical signals achieve 19 dBm in single-wavelength configuration and 21 dBm in multi-wavelength configuration, while maintaining a secure key rate above 10 kbps. This breakthrough establishes HCF as a viable platform for simultaneous high-capacity classical communication and quantum-secured data transmission, overcoming critical power limitations of existing fiber-based coexistence systems.

Journal of Optical Communications and Networking•Aug 27, 2025•1 citation

Entanglement-based quantum key distribution with data in hollow-core fiber

Yue Luo, Sheng Liu, Yun-Ru Fan +11 more

The coexistence of quantum information and classical signals in a single fiber is essential for future quantum networks that leverage the well-established optical fiber infrastructure. Although multiplexing technologies can separate quantum and classical signals, pure silica core fibers (PSCFs) remain fundamentally limited by the high nonlinearity, which generates substantial Raman scattering and four-wave mixing noise. Hollow-core fibers (HCFs), guiding light predominantly in air, offer an attractive solution with intrinsically ultra-low nonlinearity and strongly suppressed nonlinear noise. In this work, we demonstrate the entanglement-based key coexisting with data over an 18-km HCF link. We achieve time-encoded high-dimensional quantum key distribution (HD-QKD) carrying 0 dBm of bidirectional received power, corresponding to a theoretical data capacity of up to 2.3 Tbps. During 24 hours of continuous operation, an average secret key rate (SKR) of 10.56 kbps is obtained. Theoretical analysis further predicts SKRs above 135 kbps over transmission distances exceeding 200 km using state-of-the-art low-loss HCFs. These results show significantly improved performance compared with PSCF-based systems and highlight the potential of HCFs for scalable quantum-classical coexistence compatible with the architectures of established fiber-optic networks.

quant-pharXiv:2607.25331•Jul 29, 2026•0 citations

Experimental Coexistence of Quantum Key Distribution and Classical Communications over 20 km Hollow-core Fiber

Weiwen Kong, Tianqi Dou, Lipeng Feng +6 more

We experimentally demonstrate the coexistence of quantum key distribution and classical communications over a 20 km hollow-core fiber, achieving a record distance in the coexistence systems to the best of our knowledge.

•Jan 1, 2025•0 citations
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.
Experimental Demonstration of 47×800Gbps47 \times 800 \text{Gbps}47×800Gbps Classical Communication and QKD Coexistence Over 101.6 Km HCF
We experimentally demonstrate 37.6 Tbps (47×800Gbps47 \times 800 \text{Gbps}47×800Gbps) classical optical communication and quantum key distribution coexisting over a 101.6 km hollow-core fiber, achieving a record capacity and distance to the best of our knowledge. Sustained secure key rate can be maintained at around 5 kbps. ©2025 The Author(s)
The integration of quantum key distribution (QKD) with classical optical networks has emerged as a pivotal strategy for building secure communication infrastructures. However, achieving their coexistence in silica-core fibers faces inherent limitations due to nonlinear interference, particularly under high classical signal power. In this paper, we experimentally demonstrate the coexistence of classical optical transport networks and QKD over 101.6 km of hollow-core fiber (HCF) with classical power exceeding 20 dBm for the first time to the best of our knowledge. Through systematic theoretical analysis, we characterize HCF’s transmission loss and nonlinear noise generation mechanisms, revealing its unique compatibility with high-power classical–quantum coexistence compared to conventional fibers. To address spectral interference from HCF’s absorption peaks and nonlinear effects, we propose a spectrally optimized multi-stage allocation (SOMA) scheme that coordinates low-loss channel selection and noise suppression. Experimental validation shows that, under the SOMA scheme, coexisting classical signals achieve 19 dBm in single-wavelength configuration and 21 dBm in multi-wavelength configuration, while maintaining a secure key rate above 10 kbps. This breakthrough establishes HCF as a viable platform for simultaneous high-capacity classical communication and quantum-secured data transmission, overcoming critical power limitations of existing fiber-based coexistence systems.
The coexistence of quantum information and classical signals in a single fiber is essential for future quantum networks that leverage the well-established optical fiber infrastructure. Although multiplexing technologies can separate quantum and classical signals, pure silica core fibers (PSCFs) remain fundamentally limited by the high nonlinearity, which generates substantial Raman scattering and four-wave mixing noise. Hollow-core fibers (HCFs), guiding light predominantly in air, offer an attractive solution with intrinsically ultra-low nonlinearity and strongly suppressed nonlinear noise. In this work, we demonstrate the entanglement-based key coexisting with data over an 18-km HCF link. We achieve time-encoded high-dimensional quantum key distribution (HD-QKD) carrying 0 dBm of bidirectional received power, corresponding to a theoretical data capacity of up to 2.3 Tbps. During 24 hours of continuous operation, an average secret key rate (SKR) of 10.56 kbps is obtained. Theoretical analysis further predicts SKRs above 135 kbps over transmission distances exceeding 200 km using state-of-the-art low-loss HCFs. These results show significantly improved performance compared with PSCF-based systems and highlight the potential of HCFs for scalable quantum-classical coexistence compatible with the architectures of established fiber-optic networks.