Resource-efficient self-tallying quantum anonymous voting

Anonymous voting enables no one to link a vote and a voter and it has been widely used in contexts such as governmental elections and decision making in groups. In this paper we propose a resource-efficient self-tallying quantum anonymous voting (SQAV) protocol with two-particle entangled states. Similar to the first SQAV protocol with multipartite entangled states [Phys. Rev. A 94, 022333 (2016)], it possesses the properties of privacy, nonreusability, verifiability, fairness, binding, and self-tallying at the same time. We analyze its performance in a noisy quantum network. Our protocol requires $mn[1+{log}_{2}(n+1)]$ qubits to prepare the information states, and its quantum resource cost is lower than that of the first SQAV protocol, where ${n}^{2}{log}_{2}m+n{log}_{2}n$ qubits are required to prepare the information states. We also prove the optimality of our quantum resource cost. To be more practical, it is further generalized to the case with three kinds of votes including positive votes, negative votes, and abstaining from voting. Our generalized protocol requires $n(2m+1)[1+{log}_{2}(n+1)]$ qubits to prepare the information states, which also has lower quantum resource cost than that of the improved SQAV protocol [IEEE Trans. Inf. Forens. Secur. 17, 3264 (2022)], where ${n}^{2}{log}_{2}(2m+1)+n{log}_{2}n$ qubits are required to prepare the information states. In contrast to multipartite entangled states, two-particle entangled states are relatively easy to prepare, which makes the proposed protocol feasible using current technology.