A Blockchain‐Assisted Quantum Secret Sharing Framework with Function‐Level Dealer Reduction

A blockchain‐assisted quantum secret sharing (QSS) framework, denoted BQSS, is presented for function‐level dealer reduction. BQSS decomposes the conventional dealer/coordinator role into plaintext‐input, quantum‐resource, and classical‐coordination functions, and transfers the objectively verifiable coordination functions to a smart‐contract state machine. Candidate GHZ states are distributed off‐chain and sampled through stabilizer predicates; retained generation outcomes provide private mask components for a classical VSS sharing of the masked secret . The smart contract coordinates registration, active‐set freezing, commitments, deadlines, VSS evidence, reconstruction triggering, deposits, and mask openings, thereby producing a globally auditable transcript for the classical workflow. Security is analyzed under explicit system assumptions on blockchain execution, classical cryptographic soundness, measurement‐report authenticity, and dealer‐side masking correctness. The baseline instantiation adopts a public‐audit reconstruction mode for threshold‐authorized disclosure, with participant‐private opening treated as an extension. Performance is evaluated through an Ethereum‐style BN254/Groth16 on‐chain cost model and an analytical depolarizing‐plus‐loss quantum‐resource model.