Practical Quantum Key Distribution with Non-Phase-Randomized Coherent States

  title={Practical Quantum Key Distribution with Non-Phase-Randomized Coherent States},
  author={Li Liu and Yukun Wang and Emilien Lavie and Chao Wang and Arno Ricou and Fen-Zhuo Guo and Charles Ci Wen Lim},
  journal={Physical Review Applied},
Quantum key distribution (QKD) based on coherent states is well known for its implementation simplicity, but it suffers from loss-dependent attacks based on optimal unambiguous state discrimination. Crucially, previous research has suggested that coherent-state QKD is limited to short distances, typically below 100 km assuming standard optical fiber loss and system parameters. In this work, we propose a six-coherent-state phase-encoding QKD protocol that is able to tolerate the total loss of up… 

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