Paper 2023/698

A public-key based secure quantum-communication protocol using entangled qubits

Abstract

We propose a quantum algorithm that crucially involves the receiver's public-key to establish secure communication of an intended message string, using shared entangled-qubits. The public-key in question is a random bit string that proclaims the sequence of measurement basis used by the receiver. As opposed to known quantum key distribution protocols, wherein a random key string is generated at the end of the communication cycle, here the sender's intended bit string itself is communicated across securely. The quantum outlay for the proposed protocol is limited to the sender and receiver sharing pairs of entangled qubits, prepared in 𝘢 𝘱𝘳𝘪𝘰𝘳𝘪 known states, besides unitary manipulations and measurements that the sender and receiver individually perform on their respective qubits, within their confines.