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)].