Quantum key distribution cannot satisfy some users without quantum capability, so semi-quantum key distribution emerges as the times required. Semi-quantum key distribution protocol is described as Alice has quantum ability to prepare and measure qubits with an arbitrary basis, while Bob only measures qubits with the computational basis or reflects qubits to Alice. However, most existing semi-quantum key distribution protocols have been performed with low eavesdropping detection probability. In this paper, we present an innovative semi-quantum key distribution protocol with high efficiency based on EPR and single-particle hybridization, in which the specific contents of {\scriptsize CTRL} or {\scriptsize SIFT} operations have been newly defined. Then, the security analysis indicates the proposed protocol is asymptotically secure with more high eavesdropping detection probability against individual eavesdropping attacks. Moreover, the efficiency analysis shows that the presented protocol is more efficient than similar literatures.
Design and Security Analysis of Quantum Key Distribution Protocol Over Free-Space Optics Using Dual-Threshold Direct-Detection Receiver
