1. Independent Optical Frequency Combs Powered 546 km Field Test of Twin-Field Quantum Key Distribution
- Author
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Zhou, Lai, Lin, Jinping, Ge, Chengfang, Fan, Yuanbin, Yuan, Zhiliang, Dong, Hao, Liu, Yang, Ma, Di, Chen, Jiu-Peng, Jiang, Cong, Wang, Xiang-Bin, You, Li-Xing, Zhang, Qiang, and Pan, Jian-Wei
- Subjects
Quantum Physics ,Physics - Applied Physics ,Physics - Optics - Abstract
Owing to its repeater-like rate-loss scaling, twin-field quantum key distribution (TF-QKD) has repeatedly exhibited in laboratory its superiority for secure communication over record fiber lengths. Field trials pose a new set of challenges however, which must be addressed before the technology's roll-out into real-world. Here, we verify in field the viability of using independent optical frequency combs -- installed at sites separated by a straight-line distance of 300~km -- to achieve a versatile TF-QKD setup that has no need for optical frequency dissemination and thus enables an open and network-friendly fiber configuration. Over 546 and 603 km symmetric links, we record a finite-size secure key rate (SKR) of 0.53~bit/s and an asymptotic SKR of 0.12 bit/s, respectively. Of practical importance, the setup is demonstrated to support 44~km fiber asymmetry in the 452 km link. Our work marks an important step towards incorporation of long-haul fiber links into large quantum networks., Comment: To appear in Physical Review Applied
- Published
- 2024