New Arbitrated Quantum Signature Scheme without Entangled state

Arbitrated quantum signature (AQS) schemes use quantum cryptography to ensure their security, and the schemes provide that the signature receiver verifies the signature with the arbitrator's assistance. Very recently, Gao and Choi found in some previous AQS schemes, the receiver, Bob can counterfeit the signer's signature under known message. Additionally, the paper gives the security analysis of the AQS scheme, and results show that not only the receiver, but also the attacker can forge the signature in the AQS scheme. Furthermore, the signer can successfully disavow any message she ever signed. To conquer these shortcomings, this paper gives a new AQS scheme without quantum entangled state; it uses special quantum logic gate and new quantum one-time pads to ensure its security. Compares with other previous AQS schemes, the new scheme has following advantages: (1) the new scheme guarantees the receiver and the attacker cannot forge the signature; (2) Because the new scheme does not use quantum entangled states, so it can reduce the complexity of implementation and provides a higher efficiency in transmission; (3) The receiver, Bob has verified the signature's integrity, so Alice cannot disavow her having signed message.