Chinese scientists realize errors tolerate high -safety quantum key distribution

Guangming Daily Hefei, August 19 (Reporter Ding Yiming) Recently, the key laboratory of the Quantum Information of the Chinese Academy of Sciences led by Academician Guo Guangcan, a Chinese University of Science and Technology, has achieved important progress in the practical research of high -safety quantum key distribution. Professor Han Zhengfu and his collaborators of the laboratory have proposed the error and tolerated measurement equipment of high stability and high safety, and the unrelated quantum key distribution agreement with high stability and high security, and The experimental verification confirmed that the agreement has a strong tolerance ability for the non -ideal characteristics of the source, and effectively promotes the practical process of the new generation of quantum key distribution technology. Relevant research results were published online on August 3 on the well -known international academic journal "Optics".

Information security is an important theme of today's era. The quantum key distribution technology is based on the principle of quantum physics, which can realize theoretical key security key distribution. However, this theoretical security requires two important assumptions, that is, users have ideal equipment that conforms to the theoretical model description, and the detection end and source of the system that eavesdroppers cannot invade the system. Measurement equipment irrelevant quantum key distribution can immune to all potential attacks on the detection end. It is a typical protocol for a new generation of quantum key distribution technology. However, it still retains many security assumptions on the source end. For example, errors and noise in quantum modulation will violate these security assumptions, which will not only significantly reduce the performance of the quantum key distribution system, but also create for potential eavesdroppers. The opportunity to take. In a complex practical environment, users have to consume a lot of resources to monitor and calibrate the source of the source, which will not only reduce the efficiency of the implementation of the agreement, but also bring potential security issues.

In order to promote the practical application of a new generation of quantum key distribution technology, Han Zhengfu's team proposed an unreasonable agreement with high stability and high safety by incorporated the common non -ideal characteristics of the source into the security proof framework. Error tolerance measurement equipment is unrelated. The agreement is exempted from all security assumptions on the detection side, and it is also exempted from the source end of the "single -light sub -state cannot distinguish between assumptions" and "pure state assumptions". Because these two assumptions are exempted, the measurement equipment irrelevant protocol has a strong tolerance ability to signal distortion and noise in quantum modulation. After strict security analysis, the team proves that the non -ideal characteristics of these source equipment will not damage the safety of the unrelated protocol of the measurement equipment, nor will it reduce the system's security key generation rate. And high stability, two characteristics.

Han Zhengfu's team also further established the irrelevant system of measurement equipment to verify the error tolerance agreement proposed. The team first implemented the original measurement of the original protocol performance by the original measurement device by the SagnaC-AMZI encoder and the four-intensity deception state-induced modulation device, and observed the measurement of the original protocol performance by observing the measurement signal through the system. Subsequently, the team used the same system to execute error tolerated measurement equipment irrelevant quantum key distribution protocols, and the security key distribution of almost constant rate was implemented without pre -calibration of base signals.

Through the comparison of front and rear performance, it has proved the high stability characteristics of an error tolerated measurement equipment, and the important value of practical application. Because the actual quantum key system often needs to work in a complex and fast environment, it is difficult to achieve accurate and real -time calibration of the source end. It also laid the theoretical and experimental foundation for the realization of the quantum key distribution technology.

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