Nano-ridge plasmonic structural colors fabricated by roll-to-roll hot-embossing

Structural colors are now applied in many areas, like traceable anti-counterfeiting and wearable technologies, due to their durability and wide color gamut. However, the large-scale deployment of structural colors has been limited by the complexity of device structures and, subsequently, the realization of cost-effective fabrication. In this work, we introduce a plasmonic structural color based on periodical nano-ridges, which can be nano-imprinted on an aluminum-polyurethane-polyethylene terephthalate film. These aluminum nano-ridges can excite metal and dielectric hybrid waveguide modes with surface plasmonic resonance for transverse magnetic (TM) lights, resulting in broad dips in the reflection spectrum. The design and key optical features of the proposed device structures are presented. The fabricated structures show desirable features, including angle-dependent and polarization-dependent chromatic reflections. This structure could be mass-produced using a conventional roll-to-roll hot-embossing nano-imprinting process on pre-prepared films, making it suitable for low-cost anti-counterfeiting applications.