报告摘要：Practical security and performance lie on the heart of the quantum key distribution (QKD) researches. Remarkably, the recently proposed twin-field and phase-matching quantum key distribution schemes have been proven to overcome the widely-believed rate-transmittance linear bound. In practice, however, these schemes suffer from large error rates, which renders the experimental realization extremely challenging.
To relief this problem, we decouple the QKD privacy from the channel disturbance with a symmetry-based security proof technique, hence remove the limitation of secure key distribution on bit error rates. As a direct application, we show that the phase-matching scheme can yield positive key rates even with high bit error rates up to 50\%. In simulation, with typical experimental parameters, the key rate is able to break the linear bound with an error rate of 13\%. The phase-matching scheme also enjoys the measurement-device-independent property so that is it immune to all detection attacks. Parts of the work can be found in [PRX 8, 031043, (2018); PR Applied 13, 064013, (2020)].
报告人简介： 清华大学交叉信息研究院副教授，博士生导师。2003年北京大学物理学院学士，2008年多伦多大学物理系博士。先后在滑铁卢大学量子计算中心，多伦多大学，利兹大学从事博士后和访问学者。2012年到清华任教，主要从事量子密码学，量子信息基础，量子计算方向的研究。