Spin‐Dislocated Metasurface for High‐Security Optical Nested Encryption

Metasurfaces, with their compact structure and multi‐dimensional light‐manipulation capabilities, have attracted considerable attention in secure data storage and transmission. However, conventional strategies that rely on simply combining different properties of the incident light or increasing encoding complexity still struggle to simultaneously achieve high integration, large capacity, and strong robustness against unauthorized decryption. Here, a spin‐dislocated metasurface is proposed, in which image information is partitioned and encoded into two mutually displaced spin eigenstates. The spin dislocation forms a physically intrinsic and invisible security lock that prevents direct retrieval of the encoded information. Clear reconstruction of both near‐field and far‐field target images becomes possible only with the assistance of a vector coherent synthesis system (VCSS) composed of a pair of Pancharatnam–Berry (PB) phase gratings. As a proof‐of‐concept, 36‐channel far‐field holography multiplexed by polarization, orbital angular momentum (OAM), and reconstruction plane, along with a near‐field intensity distribution, is experimentally demonstrated. Furthermore, by incorporating a distinct mapping encoding mechanism, we demonstrate an optical nested encryption scheme capable of parallel message delivery and independent decryption for multiple users, which is inherently well‐suited to nanoimprinted metasurfaces. This work opens a new avenue for the design of multi‐user, high‐capacity, and high‐security optical communication systems.