An Analysis of Quantum Secure Direct Communication

Abstract

Quantum secure direct communication is a process in quantum communication to allow users to communicate securely and directly using quantum mechanics and without the need of generating and sharing secure keys. In recent years, many quantum secure direct communication (QSDC) protocols have been established and proposed. This paper seeks to explore three such QSDC protocols. The first protocol relies on hyperentanglement and complete Bell-state measurements for encoding and decoding of classical information. The second protocol relies on hyperentanglement and a complete polarization Bell-state analysis for encoding and decoding of classical information. The third protocol creates a 15-user quantum network and uses a Bell-state measurement based on the sum-frequency generation to decode classical bits. This paper will provide an in-depth look at the steps of these protocols, test these protocols in conjunction with previously designated criteria for QSDC schemes, and compare and contrast these protocols.