Jing Xu, Qian Cheng, Weng Chen-Xun, Li Bing-Hong, Chen Zhe, Wang Chen-Quan, Tang Jie, Gu Xiao-Wen, Kong Yue-Chan, Chen Tang-Sheng, Yin Hua-Lei, Jiang Dong, Niu Bin, Lu Liang-Liang
Key Laboratory of Optoelectronic Technology of Jiangsu Province, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, China.
National Laboratory of Solid-State Microstructures and School of Physics, Nanjing University, Nanjing 210093, China.
Sci Adv. 2024 Aug 23;10(34):eadp2877. doi: 10.1126/sciadv.adp2877.
Quantum communication networks are crucial for both secure communication and cryptographic networked tasks. Building quantum communication networks in a scalable and cost-effective way is essential for their widespread adoption. Here, we establish a complete polarization entanglement-based fully connected network, which features an ultrabright integrated Bragg reflection waveguide quantum source, managed by an untrusted service provider, and a streamlined polarization analysis module, which requires only one single-photon detector for each user. We perform a continuously working quantum entanglement distribution and create correlated bit strings between users. Within the framework of one-time universal hashing, we provide the experimental implementation of source-independent quantum digital signatures using imperfect keys circumventing the necessity for private amplification. We further beat the 1/3 fault tolerance bound in the Byzantine agreement, achieving unconditional security without relying on sophisticated techniques. Our results offer an affordable and practical route for addressing consensus challenges within the emerging quantum network landscape.
量子通信网络对于安全通信和加密网络任务都至关重要。以可扩展且经济高效的方式构建量子通信网络对于其广泛应用至关重要。在此，我们建立了一个完整的基于偏振纠缠的全连接网络，其特点是有一个由不可信服务提供商管理的超亮集成布拉格反射波导量子源，以及一个精简的偏振分析模块，每个用户仅需一个单光子探测器。我们进行了持续工作的量子纠缠分发，并在用户之间创建了相关比特串。在一次性通用哈希框架内，我们提供了使用不完美密钥的与源无关量子数字签名的实验实现，规避了私有放大的必要性。我们进一步突破了拜占庭协议中的1/3容错界限，在不依赖复杂技术的情况下实现了无条件安全性。我们的结果为应对新兴量子网络环境中的共识挑战提供了一条经济实惠且切实可行的途径。
