Efficient Multi-party Quantum Secret-Sharing Protocol

Context

Quantum secret sharing allows one secret dealer to divide his/her secret among different participants. Only when all the participants pool their secret pieces together can the secret be reconstructed. Quantum secret-sharing protocol can provide high security for users who need to share some secret information among some partners. It is also a useful tool in many applications such as secure operations of joint sharing of quantum money, sharing ancilla states, and distributed quantum computation.

Objective

We propose a novel multi-party quantum secret-sharing protocol (MPQSSP).

Methods

In our protocol, the dealer mixes the particle sequence of the Bell states and sends the sequence to the participants. The participants encode their secret pieces into Pauli operators, which are applied to the received particle sequence. After annularly transmitting and operating the particle sequence, the participants return the particle sequence to the dealer, who can share a secret with the partners by measuring the returned sequence with the Bell basis.

Results

The proposed MPQSSP has the merits as follows. First, its qubit efficiency can be 100% when the sample bits of the secret and the corresponding sample qubits are ignored (In our protocol when the qubit efficiency is computed, the sample bits and the corresponding Bell states used to check eavesdropping are ignored). Second, it can protect participants' privacy and interests, since the dealer cannot derive the secret piece of any participant although he/she masters the secret. Third, the participants need not perform many quantum operations and measurements to check the eavesdropping, which helps improve the efficiency of the protocol. Fourth, compared with most of the similar MPQSSPs, the quantum resources of the proposed one are relatively easier to prepare. At last, the proposed protocol has the security against various eavesdropping attacks.

Conclusion

The merits above show that Our MPQSSP is relatively more practical and efficient than similar ones.