High-capacity quantum secure direct communication based on quantum hyperdense coding with hyperentanglement

TL;DR

This paper introduces a high-capacity quantum secure direct communication protocol utilizing hyperentanglement and hyperdense coding, offering advantages in capacity and feasibility over existing methods.

Contribution

It proposes a novel QSDC protocol based on hyperentanglement and hyperdense coding, improving capacity and practical implementation feasibility.

Findings

Higher communication capacity than qubit-based protocols

More feasible than high-dimensional quantum systems

Potential for practical quantum secure communication

Abstract

We present a quantum hyperdense coding protocol with hyperentanglement in polarization and spatial-mode degrees of freedom of photons first and then give the details for a quantum secure direct communication (QSDC) protocol based on this quantum hyperdense coding protocol. This QSDC protocol has the advantage of having a higher capacity than the quantum communication protocols with a qubit system. Compared with the QSDC protocol based on superdense coding with $d$-dimensional systems, this QSDC protocol is more feasible as the preparation of a high-dimension quantum system is more difficult than that of a two-level quantum system at present.