Comparative Study of Plasmonic Colors from All-Metal Structures of Posts and Pits

Abstract

Thin-film and isolated metal nanostructures with localized plasmon resonances in the visible spectrum are promising for commercial adoption of ultrahigh resolution color printing. As metallization processes used in printing industries tend to produce thick and continuous metal coatings, challenges remain in designing structures with similar local resonances to produce colors. Here, we demonstrate color elements through surface textures on an encapsulated silver surface thus bringing plasmonic colors a step closer to commercial printing processes. We probe the chromatic range of protrusions and indentations, two possible architectures that could form on an all-metal surface, and further investigate the modulation of color when the protrusions evolve into the reversed structures of indentations. Notably, the indentations generate pitch-dependent colors; albeit protrusions generate size-dependent colors that are superior. Building upon this blueprint for all-metal plasmonic color printing, we highlight the spectral tunability of these complementary geometries through an oxidation-robust color microprint. We envision that these structures will enable economically feasible ultrahigh resolution color creation with metallic finishes on plastic films.