中国物理B ›› 2015, Vol. 24 ›› Issue (5): 50309-050309.doi: 10.1088/1674-1056/24/5/050309
权东晓, 朱畅华, 刘世全, 裴昌幸
Quan Dong-Xiao (权东晓), Zhu Chang-Hua (朱畅华), Liu Shi-Quan (刘世全), Pei Chang-Xing (裴昌幸)
摘要: We construct a circuit based on PBS and CNOT gates, which can be used to determine whether the input pulse is empty or not according to the detection result of the auxiliary state, while the input state will not be changed. The circuit can be treated as a pre-detection device. Equipping the pre-detection device in the front of the receiver of the quantum key distribution (QKD) can reduce the influence of the dark count of the detector, hence increasing the secure communication distance significantly. Simulation results show that the secure communication distance can reach 516 km and 479 km for QKD with perfect single photon source and decoy-state QKD with weak coherent photon source, respectively.
中图分类号: (Quantum communication)