| Literature DB >> 33449747 |
Yuan Cao1,2,3, Yu-Huai Li1,2,3, Kui-Xing Yang1,2,3, Yang-Fan Jiang1,2,3, Shuang-Lin Li1,2,3, Xiao-Long Hu4, Maimaiti Abulizi1,2,3, Cheng-Long Li1,2,3, Weijun Zhang5, Qi-Chao Sun1,2,3, Wei-Yue Liu1,2,3, Xiao Jiang1,2,3, Sheng-Kai Liao1,2,3, Ji-Gang Ren1,2,3, Hao Li5, Lixing You5, Zhen Wang5, Juan Yin1,2,3, Chao-Yang Lu1,2,3, Xiang-Bin Wang2,4, Qiang Zhang1,2,3, Cheng-Zhi Peng1,2,3, Jian-Wei Pan1,2,3.
Abstract
Measurement-device-independent quantum key distribution (MDI-QKD), based on two-photon interference, is immune to all attacks against the detection system and allows a QKD network with untrusted relays. Since the MDI-QKD protocol was proposed, fiber-based implementations aimed at longer distance, higher key rates, and network verification have been rapidly developed. However, owing to the effect of atmospheric turbulence, MDI-QKD over a free-space channel remains experimentally challenging. Herein, by developing a robust adaptive optics system, high-precision time synchronization and frequency locking between independent photon sources located far apart, we realized the first free-space MDI-QKD over a 19.2-km urban atmospheric channel, which well exceeds the effective atmospheric thickness. Our experiment takes the first step toward satellite-based MDI-QKD. Moreover, the technology developed herein opens the way to quantum experiments in free space involving long-distance interference of independent single photons.Year: 2020 PMID： 33449747 DOI： 10.1103/PhysRevLett.125.260503
Source DB: PubMed Journal: Phys Rev Lett ISSN： 0031-9007 Impact factor: 9.161