Data and Time April 24 , 2012, 3:00-4:15 PM
Location Sanford Fleming Building (SF), Room B560
Host Alex Wong

Measurement-device-independent quantum cryptography

Dr. Bing Qi

The Edward S. Rogers Sr. Department of Electrical and Computer Engineering (Photonics)


Quantum key distribution (QKD) protocols have been proven to be information theoretically secure based on fundamental laws in quantum mechanics. However, practical QKD systems often deviate from idealized models employed in standard security proofs and have imperfections that may lead to fatal security loopholes. Indeed, quantum hacking against practical QKD systems, particularly via detector side channel attacks, has emerged as a hot topic.
Recently, we have proposed (Physical Review Letters 108, 130503, 2012) an entirely new approach—measurement-device-independent QKD (MDI-QKD)—that can “short-circuit” all detector security loopholes. In other words, the system will be automatically immune to all detector side channel attacks. In this talk, I will review the basic idea of QKD, introduce a few successful quantum hacking schemes and present our recent work on measurement-device-independent QKD.



Dr. Bing Qi received his B.A. in Physics from Nanjing University in 1990, and Ph.D. in Optical Instrument from Dalian University of Technology in 1996. Currently, he is a senior research associate in Prof. Hoi-Kwong Lo and Prof. Li Qian’s group in Dept. of Electrical and Computer Engineering, University of Toronto.