Integrated Quad‐Color Nanoprinting and Tri‐Channel Holographic Encryption Meta‐Marks with Printable Metasurfaces

Optical metasurfaces offer innovative approaches to manipulate the amplitude, phase, frequency, and polarization of light in localized regions, thus paving the way for a viable technology that can be applied in various domains, including structural coloration, multiplexed holography, and high‐resolution displays. To address the escalating need for sophisticated encryption, a novel quadruple‐security flexible plasmonic anti‐counterfeiting platform is proposed that utilizes printable centimeter‐scale (0.6 cm) metasurfaces. These metasurfaces feature four distinct signatures: They appear as color images under ambient incoherent white light, while projecting up to three different holograms under red, green, or blue circularly polarized laser illumination. Such holographic color nanoprintings are not only easily authenticated but also difficult to imitate, offering enhanced security in anti‐counterfeiting applications. The design of these multifunctional metasurfaces, which encode information solely in the surface relief of a single polymeric material with a silver coating, allows for efficient mass production through UV nanoimprinting lithography. Given the superior performance of these multifunctional plasmonic metasurfaces, this work presents tremendous potential in various fields such as multi‐level information security, cost‐effective anti‐counterfeiting, and many others.