International Journal of Quantum Information
A NEW DETECTION STRATEGY FOR TWO-STEP QSDC PROTOCOL BASED ON THE FIVE-PARTICLE CLUSTER STATE
Jian Li, Lingyun Li, Sicong Chen, Xudong Liu
Abstract
Detection efficiency of a quantum secure direct communication (QSDC) protocol is crucial. Therefore, it is necessary to improve the security of these protocols on the basis of new detection strategies. In this paper, a new strategy based on the five-particle cluster state is proposed, and applied to the two-step QSDC protocol. Moreover, information theoretical method and numerical analysis is applied to analyze the security of the improved protocol. If Eve intends to eavesdrop all of the information, the probability of being detected reaches up to 7/8, whereas the same is 0.5 in the original protocol. It is concluded that using the new detection strategy in the two-step QSDC protocol is more secure than using the original protocol when the quantum key distribution (QKD) protocol is considered.