Physica Scripta
A ( t,n ) threshold quantum secret sharing with cheat identification and authenticity
Nancy Mittal, Sanjeev Kumar
Abstract
Abstract In this paper, we introduce an authenticable quantum secret sharing protocol by utilizing unitary diagonal operator and quantum SUM gate. Here, dealer distributes quantum and classical information simultaneously to participants. The cheat-detection mechanism is designed to identify and expose any malicious actions by participants. During this process, each subsequent participant can detect and recognize deceptive behaviour from dishonest members. To ensure that only legitimate participants are involved in the protocol, we introduce an identity authentication mechanism, where the dealer and each participant share a pair of secret PIN sequences. The implementation of the proposed scheme on the IBM quantum platform (restricted to d = 2) demonstrates its operational correctness and feasibility. Noise-aware simulations under realistic NISQ conditions show that, although performance degrades with increasing noise, the correct outcome remains dominant, indicating robust behaviour in the presence of decoherence, gate errors, and measurement imperfections. Additionally, a complementary analysis is performed under different noise environments, including dit-flip noise, d-phase-flip noise, and depolarizing noise. The obtained results indicate that the efficiency of the proposed protocol decreases with increasing channel noise parameter, with distinct performance variations observed across all the noise models. Furthermore, this work takes into account the situation in which at least t out of the n participants can use the Lagrange interpolation to recover the secret classical and quantum information. The security analysis demonstrates that the proposed protocol is resilient to intercept-resend, collusion, entangle-measure, forgery and denial attacks.