Semantic quantum secure direct communication

Quantum communication has reached a rate bottleneck, yet enhancing its throughput remains of profound significance. Here, we propose a scheme termed semantic quantum secure direct communication (QSDC), which is a novel paradigm integrating semantic communication with QSDC to realize highly efficient, task-oriented, and intrinsically secure information transmission. In semantic QSDC, meaningful semantic content is directly encoded into quantum states, whereby the fundamental laws of quantum physics guarantee inherent eavesdropping-detection capability and information-theoretic security. By harnessing semantic compression and artificial intelligence–assisted encoding strategies, this approach surpasses the intrinsic rate constraints of conventional QSDC. Simulation results show that semantic QSDC can surpass the Shannonian mutual information bound compared with conventional QSDC systems and demonstrate its potential to break through the linear rate-transmittance bound of quantum communication. These findings pave the way for high-rate secure communication.