Bell state-based semi-quantum signature scheme with arbitrator

Semi-quantum signature is an important research topic in quantum cryptography. Based on the Bell states, a semi-quantum signature scheme with arbitrator is proposed. In our scheme, the quantum signer signs the message by encoding the ciphtext with the Bell states and performing the controlled NOT gate on the particles, while the signature receiver and arbitrator corporately verify the signature by measuring the received qubits with Z-basis. Compared with the similar schemes, ours has the better performances as follows. (1) It can be proved to be information-theoretically secure. It has the strong undeniability property. (2) The signer is a quantum partner, while both the signature receiver and the arbitrator are classical partners. (3) The signer needn’t share any private key with the receiver. (4) The scheme is based on Bell state, which is relatively easier to be prepared than the other entanglement resources used in the similar schemes. (5) It has better qubit efficiency. Therefore, our scheme has better performances in security, practicability and efficiency than the similar schemes.