Efficient Quantum Signature and Its Application in On-line Quantum Payment System

Two arbitrated quantum signature schemes, one with message recovery and the other with appendix, are proposed. The most significant property of the proposed schemes is that both the signatory and the receiver can share and use a long-term secret key with the arbitrator by utilizing the key together with a random number. While in previous quantum signature schemes, the shared key could be used only once, and thus each time when a signatory needs to sign, the signatory and the receiver have to obtain a new key shared with the arbitrator through quantum key distribution protocol. Results show that the presented schemes could be provably secure under the Unbiased-Chosen Basis (UCB) assumption. Moreover, we applies the quantum signature to quantum payment and propose an on-line quantum payment system.