Enhanced Coexistence of Quantum Key Distribution and Classical Communication over Hollow-Core and Multi-Core Fibers
Weiwen Kong,
Yongmei Sun,
Tianqi Dou,
Yuheng Xie,
Zhenhua Li,
Yaoxian Gao,
Qi Zhao,
Na Chen,
Wenpeng Gao,
Yuanchen Hao,
Peizhe Han,
Yang Liu,
Jianjun Tang
Affiliations
Weiwen Kong
China Telecom Research Institute, Beijing 102200, China
Yongmei Sun
The State Key Laboratory of Information Photonics and Optical Communications, School of Information and Communication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China
Tianqi Dou
China Telecom Research Institute, Beijing 102200, China
Yuheng Xie
China Telecom Research Institute, Beijing 102200, China
Zhenhua Li
China Telecom Research Institute, Beijing 102200, China
Yaoxian Gao
The State Key Laboratory of Information Photonics and Optical Communications, School of Information and Communication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China
Qi Zhao
China Telecom Research Institute, Beijing 102200, China
Na Chen
China Telecom Research Institute, Beijing 102200, China
Wenpeng Gao
China Telecom Research Institute, Beijing 102200, China
Yuanchen Hao
China Telecom Research Institute, Beijing 102200, China
Peizhe Han
China Telecom Research Institute, Beijing 102200, China
Yang Liu
China Telecom Research Institute, Beijing 102200, China
Jianjun Tang
China Telecom Research Institute, Beijing 102200, China
In this paper, we investigate the impact of classical optical communications in quantum key distribution (QKD) over hollow-core fiber (HCF), multi-core fiber (MCF) and single-core fiber (SCF) and propose wavelength allocation schemes to enhance QKD performance. Firstly, we theoretically analyze noise interference in QKD over HCF, MCF and SCF, such as spontaneous Raman scattering (SpRS) and four-wave mixing (FWM). To mitigate these noise types and optimize QKD performance, we propose a joint noise suppression wavelength allocation (JSWA) scheme. FWM noise suppression wavelength allocation and Raman noise suppression wavelength allocation are also proposed for comparison. The JSWA scheme indicates a significant enhancement in extending the simultaneous transmission distance of classical signals and QKD, reaching approximately 100 km in HCF and 165 km in MCF under a classical power per channel of 10 dBm. Therefore, MCF offers a longer secure transmission distance compared with HCF when classical signals and QKD coexist in the C-band. However, when classical signals are in the C-band and QKD operates in the O-band, the performance of QKD in HCF surpasses that in MCF. This research establishes technical foundations for the design and deployment of QKD optical networks.
