Quantum dialogue based on quantum encryption with single photons in both polarization and spatial-modedegrees of freedom

Abstract

In this paper, a novel information-leakage-resistant quantum dialogue (QD) protocol with single photons in both polarization and spatial-mode degrees of freedom is proposed. This protocol utilizes quantum encryption technology to overcome the information leakage problem; the protocol utilizes quantum encryption and decoy photon technologies to dually protect the single photons with two degrees of freedom used for encoding two communicants' private classical bits, and makes the initial states of the single photons with two degrees of freedom for encoding shared between two communicants through quantum key encryption and decryption. The information-theoretical efficiency of this protocol is 40%.