Deterministic Quantum Secure Direct Communication Protocol Based on Omega State

A quantum secure direct communication (QSDC) protocol is presented. In the proposed protocol, the omega state is introduced to detect the eavesdropping during the quantum communication, eavesdropping behaviors will change the state of the omega state, and the sender Alice and the receiver Bob detect eavesdropping through the state measurement results. The relationship between the amount of information that the eavesdropper gets and the probability of being detected is also given. Compared with the original QSDC protocol based on the Bell state, when the same amount of information is obtained, the eavesdropper must face a higher detection probability in the proposed protocol, and the eavesdropper mostly can obtain 0.676 (bit) of information. The security analysis is also given, and the result indicates that the proposed protocol is more secure. A simulation based on the law of large number and the Monte Carlo method is also given, and the mean square error is introduced to describe the similarity between the simulation data and the theoretical value. The simulation result indicates that the proposed security in an ideal environment and the security analysis are correct, and the proposed protocol is more secure by sending more quantum particles in detecting eavesdropping.