Quantum communication, based on the quantum physics, can provide information theoretical security. Building a global quantum network is one ultimate goal for the research of quantum information. Here, this talk will review the progress for quantum communication in China, including quantum key distribution over metropolitan area with untrustful relay, field test of quantum entanglement swapping over metropolitan network, the 2000 km quantum key distribution main trunk line, and satellite based quantum communication.
Quantum communication, based on the quantum physics, can provide information theoretical security. Building a global quantum network is one ultimate goal for the research of quantum information. Here, this talk will review the progress for quantum communication in China, including quantum key distribution over metropolitan area with untrustful relay, field test of quantum entanglement swapping over metropolitan network, the 2000 km quantum key distribution main trunk line, and satellite based quantum communication.
Quantum communication, based on the quantum physics, can provide information theoretical security. The gap between ideal devices and realistic setups, however, has raised various security loopholes, which have become the targets of many attacks and obstacles against its deployment and applications. I shall review the various efforts towards secure QKD system with practical devices over the society. Then I shall provide details about the deployed quantum communication systems in China, including metropolitan, backbone and satellite based international network, the technology challenging, the performance and an outlook.
Quantum communication based on quantum mechanics is a secure communication technology,which can provide unconditional security between communication parties in principle. Recently,quantum communication technology and its practical engineering have been regarded by many counties and regions such as the US,European Union,China and Japan. With the engineering development of quantum communication technology,it has been progressing from point-to-point communications to network applications,including local area networks and wide area networks. Furthermore,global quantum communication is developing. In the review,we summarize in detail the development of the quantum communication networks built by various countries,and introduce the plans of quantum satellites.
China has achieved major scientific accomplishments since embarking in 2001 on a journey to harness the vast potential of quantum mechanics in information security and military applications. Chinese scientists claimed success in satellite-based entanglement distribution in June 2017. Three months later, in September 2017, the 2,000-kilometer Quantum Communication Line between Shanghai and Beijing opened the world’s first trunk line of secure quantum telecommunications. China’s political leadership has demonstrated its interest and support in this very expensive endeavor, owing to the strategic and military applications of quantum cryptography, quantum computing, and quantum metrology for highly secure communications, stealth submarine operations, and military code breaking. This article explores the rapid development and evolution of research in quantum communications in China, the critical role of political leadership, and the immense opportunities it holds in the military domain.
Quantum computing poses a serious threat to classical cryptographic algorithms based on computational complexity. Quantum key distribution (QKD), utilizing the principles of quantum mechanics, enables secure key exchange and has been proven to be an essential technology to resist the threat of quantum computing. China attaches great importance to the construction of QKD network to deal with this threat. In 2020, China established an integrated space-to-ground quantum communication network, which includes 32 backbone nodes and 4 metropolitan networks. Here we introduce China’s latest progress in the deployment of QKD networks, called the China Quantum Communication Network (CN-QCN). CN-QCN is an operational, long-range, and trusted-relay-based QKD network spanning over 10,000 kilometers, incorporating 145 fiber backbone nodes, and 20 metropolitan networks, which cover 17 provinces and 80 cities. Moreover, the network has deployed 6 ground stations linked with Jinan-1 quantum microsatellite. CN-QCN has not only surpassed its predecessor in scale, but also made significant advancements in multi-type QKD hybrid networking and long-range quantum network operation and maintenance. We present the network architecture, QKD implementation, and long-term performance of CN-QCN in this paper. This work lays the foundation for widespread applications of QKD in China.
Entanglement distribution is a fundamental building block of quantum communication networks, enabling the secure and reliable exchange of quantum information over long distances. Unlike classical communication, quantum networks exploit the unique properties of quantum entanglement to support applications such as quantum key distribution, quantum teleportation, distributed quantum computing, and networked quantum sensing. Although significant progress has been made in recent years, the efficient generation, transmission, and preservation of entangled states remain major research challenges due to photon loss, decoherence, and limitations in current communication infrastructure.This review provides a comprehensive overview of entanglement distribution in quantum communication networks, focusing on the technologies that enable practical implementation and the latest experimental developments. It discusses key approaches for generating and distributing entangled photons through optical fibers, free-space links, and satellite-based communication, together with supporting technologies such as quantum repeaters, quantum memories, and photonic devices. The review also examines recent experimental demonstrations that have advanced long-distance quantum communication while highlighting the technical barriers that must be overcome for large-scale deployment. Finally, emerging applications and future research directions are presented, including the development of scalable quantum networks, the quantum internet, and secure global communication systems. This review aims to provide researchers and students with a clear understanding of the current state of entanglement distribution and its growing role in next-generation quantum communication technologies.