Research On Quantum Secret Sharing Protocols Based On Multi-particle Entangled States

Quantum secret sharing is an important branch of quantum communication that shares classical or quantum information. Suppose Alice wants to share her information with Bob and Charlie, she can accomplish this aim safely by using quantum key distribution protocol that is not the best way to complete the secret sharing since it wastes resources. Quantum secret sharing protocol is a solution with lesser resources and more efficiency and security.In this paper, we use some multi-particle states as carriers to design three quantum secret sharing protocols. In the first protocol, we utilize reusable asymmetric three-particle entangled states as carrier that the sender encodes information into the carrier with CNOT operation and the receiver reuses CNOT operation to remove entanglement for completing quantum secret sharing. In order to check the existence of an eavesdropper, we randomly insert decoy particles for detecting eavesdropping, it shows that the protocol can effectively prevent eavesdropping and against entanglement spoofing attacks. In the second protocol, we utilize cluster states as carrier that the sender entangles unknown quantum states with cluster states and carries out Bell measurements. For more security, we insert decoy particles randomly to detect eavesdropping. In the third protocol, we use a composite quantum states consisted by two GHZ states as the quantum channel and share a three-particle GHZ state, they can recover secret and complete secret sharing of unknown quantum state after Alice carries out Bell measurements for two times, Bob carries out Bell measurements for one time and Charlie completes the corresponding unitary operations.