Decoy state quantum secret sharing protocol with collective detection

The quantum secret sharing protocol with collective detection has garnered significant attention due to its high communication efficiency and low demands on agent capabilities. However, practical implementations face challenges such as intolerance to channel loss and insufficient practical security analysis. To address these issues, this paper proposes a decoy quantum secret sharing protocol with collective detection. First, we analyze the potential security threats posed by multi-photon signals and propose two attack methods, rigorously demonstrating their severe impact on protocol security. Subsequently, to mitigate the adverse effects of multi-photon signals, we introduce a decoy state strategy to enhance the protocol's reliability under non-ideal conditions. Finally, detailed security analysis against the proposed attacks confirms that the improved protocol effectively resists both attacks even in non-ideal scenarios, thereby ensuring secure and reliable quantum secret sharing.