Angular-dependent asymmetric plasmonic resonance of inclined nanopillars using stencil nanolithography

Researches on polarization using metamaterials are applied in various fields. In particular, asymmetrically aligned nanostructured arrays have unique applications because they support interesting optical properties that differ from symmetrical structures. However, conventional nanostructures like 2D hole arrays rely on E-beam lithography or focused ion beam methods requiring complex processes, and they are not suitable for fabricating 3D nanostructures. In this work, we demonstrated the inclined-gold nanopillar arrays through one-step stencil lithography on 0.5mm x 0.5mm area. The angle between the substrate and the vapor flux was precisely controlled by tilting the substrate to form an inclined nanorod. The polarization direction dependences of inclined pillar arrays are experimentally measured in the visible regime. Unlike symmetric structures, breaking of symmetry between nanostructures and electromagnetic fields leads to polarization direction dependence plasmonic effect in asymmetric structure. We experimentally analyzed that reflectance is adjustable by controlling the plasmon coupling distribution of the localized surface plasmon resonance occurring on the surface of the nanostructure using polarization on the asymmetric nanostructure. Based on this concept, we expect that this concept is applicable in the field of three-dimensional metasurface, polarization-controlled color printing, and polarization detecting system.