Self-assembled plasmonic coaxial nanocavities for high-definition broadangle coloring in reflection and transmission

Resonant spectral scattering from metallic nanostructures is an attractive alternative
approach to produce colors instead of using chemical pigments. In this work, we developed a technological platform based on self-assembled arrays of coaxial plasmonic resonators for generating the bright color gamut over the entire visible spectral range in both reflection and transmission offering the potential for ultra-high definition coloring. Self-assembly approach providing highly efficient mode engineering provides an opportunity to achieve coloring effects over large areas with the local colors being controlled by post-processing. Unlike the approaches using the nanostructure periodicity to define color, the developed method employs the mode engineering based on the localized plasmon resonances in the nanocavities, therefore, providing a broad angular response and viewing angles of up to 40°. With the nanoscale dimensions of the proposed color pixels and increased viewing angular range, the proposed approach allows to achieve large-area color patterns with local coloring controlled by postprocessing important for anticounterfeiting and artistic applications.