Compression-Encrypted Meta-Optics for Storage Efficiency and Security Enhancement

Abstract

Information security is of vital importance in daily life, stimulating various cryptographic strategies to protect data from leaking. Among them, metasurface-based optical encryption is an excellent candidate because of its unique features, including numerous encoding channels and incomparable light-field manipulation ability. However, for state-of-the-art metasurface encryption, it is still critical to further improve its storage efficiency with high security for practical information-storage applications. Here, combining data compression and optical encryption, compression-encrypted meta-optics (CEM) is proposed to improve the regular metasurface storage efficiency by an order of magnitude while maintaining high information security. Utilizing lossless compression algorithms, the plaintexts are re-encoded into nonintuitive ciphertexts and keys with much less data volume (∼1/10), thus providing the first security barrier and increasing storage efficiency. Moreover, the polarization-encrypted metasurfaces also protect the ciphertexts from direct observation, providing a second security barrier. Overall, such a CEM with two security barriers significantly improves the optical storage efficiency and presents a novel route for potential applications in next-generation optical information storage/encryption.