Prof. PAN Jianwei, Prof. XU Feihu and Prof. ZHANG Qiang from University of Science and Technology of China (USTC), collaborating with Prof. MA Xiongfeng from Tsinghua University and Prof. Hoi-Kwong Lo from University of Toronto, were invited to publish a review titled Secure quantum key distribution with realistic devices in the Reviews of Modern Physics on May 26th.
Quantum communication is an important branch of quantum information science. It refers to the communication technology that uses quantum bits as information carrier to carry out information interaction.
One of the most typical applications of quantum communication is quantum key distribution (QKD). QKD can provide a theoretically secure means of communication, which is the only communication method whose security has been strictly proved so far. It is also the first quantum information technology from laboratory to practical application, becoming one of the most dynamic frontiers in physics.
In recent years, with the development of practical research of QKD, the realistic security of QKD has been widely concerned in the world. The potential security risks and solutions introduced by devices in actual systems that do not fully conform to the mathematical model of the protocol was mainly studied. It’s worth mentioning that Prof. PAN's team experimentally realized several important new protocols in the world for the first time.
This paper reviews the development history of quantum cryptography in detail, discusses the practical security of quantum key distribution in depth, and forecasts the future development trend of QKD technology. Throughout more than 30 years of joint efforts of global researchers, the security of practical quantum cryptography has been established. In particular, the proposed QKD protocol, such as measurement-device independent (MDI) protocol, removes the security risks that may occur in the physical realization of quantum cryptography, paving the way for the quantum cryptography based on real devices.
The four initial MDI-QKD experiments. (a) Proof-of-principle MDI-QKD with time-bin encoding. (b) Full MDI-QKD implementation with random modulations of states and decoy intensities based on time-bin encoding. (c) Proof-of-principle MDI-QKD with polarization encoding. (d) Full MDI-QKD with random modulations of states and decoy intensities based on polarization encoding. (Image by A. Rubenok, LIU Yang, T. Ferreira da Silva, TANG Zhiyuan, et. al.)
A special comment published in the journal states that this review gives both sides of the story, with the current best theory of quantum security, and an extensive survey of what makes quantum cryptosystem safe in practice.
Reviews of Modern Physics is the most authoritative review journal in the field of physics with an average impact factor of over 40 in the past five years. Only about 40 academic papers are published every year. This is the second review paper published by Prof. PAN’s team, and is also China’s second review paper published in this journal in quantum information science, marking that China continues to maintain its international leading position in quantum communication.
Paper Link:
https://journals.aps.org/rmp/abstract/10.1103/RevModPhys.92.025002
(Written by LU Hongyu, edited by JIANG Pengcen, USTC News Center)