Quantum Key Distribution Protocol Based on Odd Coherent Sources and Orbital Angular Momentum

In view of the problem of the low key generation rate for the measurement device independent quantum key distribution (MDEQKD) protocol based on weak coherent sources (WCS) and orbital angular momentum (OAM), the MDI-QKD protocol based on odd coherent sources (OCS) and OAM is investigated, and its performance and parameters arc analyzed. The relationships between key generation rate, quality factor of detector and secure transmission distance arc investigated. The performance comparison between the MDI-QKD protocol based on OCS and OAM and the MDI-QKD protocol based on WCS and OAM is compared. The simulation results show that the key generation rate decreases with the increase of secure transmission distance. The adoption of OCS makes up the deficiency of WCS and reduces the photon number greatly, while the adoption of OAM can solve the problem of the dependence defect of the base and increase the maximum secure transmission distance, which provides an important theoretical reference for the practical quantum key distribution protocol.