Application and use of quantum communication
Quantum communication has absolute security characteristics that traditional communication methods do not have. It not only has great application value and prospect in the fields of national security, finance and other information security, but also gradually enters people's daily life.
In order to make quantum communication from theory to reality, scientists at home and abroad have done a lot of research work since 1990s. Since 1993, researchers from IBM in the United States put forward the theory of quantum communication, both the National Science Foundation and the Defense Advanced Research Projects Agency have conducted in-depth research on this project. 1999, the European union concentrated international efforts on quantum communication, with as many as 12 research projects, and the Japanese Ministry of Posts and Telecommunications regarded quantum communication as a strategic project in 2 1 century.
China has been engaged in the research of quantum optics since 1980s. In recent years, the Quantum Research Group of China University of Science and Technology has made outstanding achievements in quantum communication.
In 2003, scholars from South Korea, China, Canada and other countries put forward a theoretical scheme of tricking quantum cryptography, which completely solved the problem that the security rate of quantum communication decreased seriously with the increase of distance under the conditions of real system and existing technology.
In the summer of 2006, Professor Pan Jianwei of the University of Science and Technology of China, the Los Alamos National Laboratory of the United States, and the joint research group of the University of Munich and the University of Vienna in Europe independently realized the decoy scheme, and at the same time realized the decoy quantum key distribution experiment exceeding 100 km, thus opening the door to the application of quantum communication.
At the end of 2008, the research team in Pan Jianwei successfully developed the optical fiber quantum communication prototype system based on decoy state, and successfully established the world's first 3-node chain optical quantum telephone network in Hefei, becoming one of the two teams (the other is the European joint experimental team) reporting the absolutely safe and practical quantum communication network in the world.
In September, 2009, Pan Jianwei scientific research team built the world's first all-pass quantum communication network based on the 3-node chain optical quantum telephone network, and realized real-time voice quantum secure communication for the first time. This achievement ranks in the international advanced level among similar products, which indicates that China has reached the industrialization requirements in the key technologies of metropolitan quantum networks.
All-pass quantum communication network is a five-node star-shaped quantum communication network, which overcomes the instability of quantum signal transmission on commercial optical fiber, which is the main technical obstacle of the practical application of quantum secure communication technology, and realizes the simultaneous communication of two users without affecting each other for the first time. The distance between users of the network can reach 20 kilometers, which can cover a medium-sized city; It accommodates two important quantum communication networking modes, interconnection and trusted relay, and realizes the communication authorization management of superior users to subordinate users.
This achievement fully demonstrated and tested the networking and expansion ability of quantum communication system for the first time, which marked the maturity of large-scale scalable network quantum communication technology and promoted the practical and industrialized process of quantum communication. It is said that Pan Jianwei team will cooperate with the 38th Institute of China Electronics Technology Corporation and other institutions to start the demonstration project of 40-node quantum communication network in Hefei and surrounding areas, so as to accumulate engineering experience for the large-scale application of quantum communication.