All‐or‐Nothing Quantum Oblivious Transfer for Unknown Unitary Operations

In this paper, we propose a resource‐efficient all‐or‐nothing oblivious transfer (OT) protocol for unknown single‐qubit unitary operations. To the best of our knowledge, this is the first construction of all‐or‐nothing OT for unknown unitary operations. In contrast to the trivial solution by combining all‐or‐nothing OT for classical messages and bidirectional quantum state teleportation, our protocol is more resource‐efficient, i.e., it only requires the consumption of two shared Bell states, two‐bit classical communication from Alice to Bob and at most one‐bit classical communication from Bob to Alice. In addition, the use of shared Bell states and simple quantum operations makes the proposed protocol feasible with current technology. Theoretical analysis and experimental simulation on IBM Qiskit simulator show the correctness of our protocol. Our results extend the application of OT protocols in privacy‐preserving distributed quantum computing.