Long-distance quantum key distribution with continuous variables

Anthony Leverrier, Philippe Grangier

Eleni Diamanti, Paul Jouguet, Sébastien Kunz-Jacques +2 more

张永生, 郭光灿

S. Nibedita Swain, Ryan J. Marshman, Josephine Dias +2 more

Noiseless linear amplifiers (NLAs) serve as an effective means to enable long-distance continuous-variable (CV) quantum key distribution (QKD), even under realistic conditions with non-unit reconciliation efficiency. Separately, unitary averaging has been suggested to mitigate some stochastic noise, including phase noise in continuous-variable states. In this work, we combine these two protocols to simultaneously compensate for thermal-loss effects and suppress phase noise, thereby enabling long-distance CV QKD that surpasses the repeaterless bound, the fundamental rate-distance limit, for repeaterless quantum communication systems.

Paul Jouguet, Sébastien Kunz-Jacques, Anthony Leverrier +2 more

Khatereh Jafari, Mojtaba Golshani, Alireza Bahrampour