Large‐Area, Optical Variable‐Color Metasurfaces Based on Pixelated Plasmonic Nanogratings

Abstract Color printing based on plasmonic nanostructures has attracted much attention due to its broad potential applications. It is still an open question regarding how to achieve large‐area plasmonic colors for practical use. In this study, large‐area plasmonic metasurfaces that incorporate a dielectric grating, an aluminum nanopatch array, and a silicon nitride layer are designed and fabricated. The asymmetric geometry of the metasurfaces produces a strong asymmetry‐induced color rendering effect, wherein different transmitted colors are observed in perpendicular planes with the same incident angle. Originating from surface plasmonic resonance and a guided mode resonance, a transmission efficiency of ≈60% is achieved. Furthermore, distinctive colors covering the entire visible range are generated by varying the grating period. Remarkably, large‐area colorful surfaces based on pixelated nanogratings with different periods can be fabricated using continuously variable spatial frequency photolithography. The experimental results coincide with simulations and show great potential for various applications such as large‐area color printing and anti‐counterfeiting certifications.