Mode-pairing quantum key distribution

NExT Forum:Quantum communication technology and applications

【講者】 Xiongfeng Ma, Associate Professor, Tsinghua University
【講題】Mode-pairing quantum key distribution
【摘要】 Quantum key distribution can establish information-theoretically secure keys based on quantum physics. Recently, schemes based on single-photon interference have been proposed to improve the key rate to $R=O(\sqrt{\eta})$ by overcoming the point-to-point secret key capacity bound with interferometers. Unfortunately, all of these schemes require challenging global phase locking to realize a stable long-arm single-photon interferometer with a precision of approximately 100 nm over fibers that are hundreds of kilometers long. In this talk, I shall present a mode-pairing measurement-device-independent quantum key distribution scheme in which the encoded key bits and bases are determined during data post-processing. Using conventional second-order interference, this scheme can achieve a key rate of $R=O(\sqrt{\eta})$ without global phase-locking when the local phase fluctuation is mild. The work can be found in [Nature Comm. 13, 3903, (2022)], see also its experimental demonstration [arXiv:2208.05649, accepted by PRL].

Organizer:鴻海研究院HHRI、台大量子科學及工程研究中心Center for Quantum Science and Engineering
Co-Organizer:財團法人人工智慧科技基金會AIF 、國家理論科學研究中心物理組NCTS Physics