近日，中国科学技术大学潘建伟团队实现了基于单原子实现跨越100公里的设备无关量子密钥分配。相关论文于2026年2月5日发表在《科学》杂志上。

设备无关量子密钥分配是量子互联网的核心应用之一。

研究组报道了在通过100千米光纤连接的两个单原子节点间实现设备无关量子密钥分配的实验。为提升纠缠速率，该实验采用单光子干涉实现纠缠预示，并利用量子频率转换降低光纤损耗。通过定制化的里德伯激发发射方案，在未引入噪声的前提下有效抑制了原子中的光子反冲效应。

研究组实现了高达100千米光纤距离的高保真度原子-原子纠缠态，并获得渐进式正密钥率。在11千米距离的624小时实验中，累计制备120万个预示贝尔纠缠对，经估算可提取的有限长安全密钥率为每事件0.112比特（可抵御一般攻击）。该研究成果弥合了原理性量子网络实验与实际应用之间的鸿沟。

附：英文原文

Title: Device-independent quantum key distribution over 100 km with single atoms

Author: Bo-Wei Lu, Chao-Wei Yang, Run-Qi Wang, Bo-Feng Gao, Yi-Zheng Zhen, Zhen-Gang Wang, Jia-Kai Shi, Zhong-Qi Ren, Thomas A. Hahn, Ernest Y.-Z. Tan, Xiu-Ping Xie, Ming-Yang Zheng, Xiao Jiang, Jun Zhang, Feihu Xu, Qiang Zhang, Xiao-Hui Bao, Jian-Wei Pan

Issue&Volume: 2026-02-05

Abstract: Device-independent quantum key distribution (DI-QKD) is a key application of the quantum internet. We report the realization of DI-QKD between two single-atom nodes linked by 100–kilometer (km) fibers. To improve the entangling rate, single-photon interference is leveraged for entanglement heralding, and quantum frequency conversion is used to reduce fiber loss. A tailored Rydberg-based emission scheme suppresses the photon recoil effect on the atom without introducing noise. We achieved high-fidelity atom-atom entanglement and positive asymptotic key rates for fiber lengths up to 100 km. At 11 km, 1.2 million heralded Bell pairs were prepared over 624 hours, yielding an estimated extractable finite-size secure key rate of 0.112 bits per event against general attacks. Our results close the gap between proof-of-principle quantum network experiments and real-world applications.

DOI: aec6243

Source: https://www.science.org/doi/10.1126/science.aec6243