Encrypted metasurfaces with inherent asymmetric-like digitized keys under decoupled near-field parameters
摘要
The modulation of the light field by metasurfaces in near-field remains constrained by the coupling of cross-polarization components. This limits the storage space for ciphertexts with orthogonal polarization states. Our proposal introduces a transmission model with layered-control theory, which realizes decoupled states of anti-diagonal entries of meta-molecules in Jones matrices, granting us the ability to modulate cross-polarization components, thus providing a feasible platform for packet transmission or other creative algorithms. Two interlinked distinct logics are strategically constructed in the loading and detecting information processes, achieving asymmetric-like encryptions. It conceals encrypted messages within spatial light field distributions with precise logical rules which can be derived into form of logical expressions as mathematical keys, mitigating the risk of direct data extraction from metasurfaces. This research refines the matching of different light fields and information, expands the modulation parameters and introduces digitized keys for encrypted metasurfaces.