An improved quantum key distribution based on lucas-valued oribital angular momentum states

We propose an improved quantum key distribution (QKD) protocol based on orbital angular momentum (OAM) entangled states. Three Lucas-valued OAM entangled photons are generated by two cascaded spontaneous parameter down-conversion processes. Two photons are detained and detected by Alice, while the other is transmitted to Bob and then detected. A new scheme is designed to sift the original key bits. Compared to existing protocols, we believe our protocol greatly improves coding efficiency and is verifiable. The analysis results show that our protocol is immune to the photon-number-splitting attack, the intercept-resend attack and the classical information leakage. This work provides an efficient path to high-dimensional QKD systems.