Three-party quantum privacy comparison protocol based on classical-quantum authentication channel

With the help of semi-honest third party , a new quantum privacy comparison (QPC) protocol is proposed, which can compare the equality of the secrets of three participants without disclosing the secret value. At present, QPC protocols using different quantum states have been proposed. If complex quantum states are used in QPC protocol, more expensive equipment or more complex methods will be required to generate these quantum states, which may reduce efficiency and increase cost. In order to improve the availability of the protocol, a QPC protocol based on classical-quantum authentication channel is proposed in this paper. The protocol takes Bell state as quantum resource and uses single-particle measurement technology to measure particles, so the protocol enables participants to compare quantum privacy without expensive quantum devices. Finally, in order to ensure the security of the protocol, we use decoy photon technology and quantum key distribution technology to encrypt, so that the protocol can resist external attacks and participant attacks.