Provably secure arbitrated-quantum signature

Although the researchers have proposed many arbitrator quantum signature (AQS) for various applications in practice, the security proof of most AQSs was not strictly presented. Many results have shown that the AQS schemes without strict security proof may be broken by various measurement and forgery attacks. Therefore, a secure AQS should strictly put its security on the quantum theorems and principles. Based on the non-orthogonal entangled-triple sequence, an AQS with provable security is proposed. First, the theoretical security proof of our AQS is presented. Second, we prove the non-cloning theorem for the entangled-triple sequence. Third, by using the non-cloning property of the entangled-triple particle, we prove the new AQS signature cannot be forged. At last, the non-repudiation of the proposed AQS is analyzed. We showed that if an adversary can break the signature, his/her actions will violate some quantum principles. The security proof of the proposed signature scheme also shows the idea of provable security for a quantum signature. On the other hand, in the proposed scheme, the partners need not perform the probabilistic quantum state comparison test. It has better qubit efficiency. Therefore, compared with the other similar schemes, ours has the better merits in security and efficiency.