Enhancing the light transmission of plasmonic metamaterials through polygonal aperture arrays

While plasmonic metamaterials find numerous applications in the field of nanophotonic devices, a device may work as a normal or plasmonic device, depending on whether it operates at the resonance mode. In this paper, the extraordinary light transmission through coaxial polygonal aperture arrays, including circle, hexagon, square, and triangle geometries, is studied using FDTD simulation. Circular, hexagonal and squared aperture arrays have similar high transmission rate, while triangular aperture array has considerably lower transmission rate. It is found that the transmission peaks reflect the resonance modes propagating along the direction of neighboring apertures. We hence rearrange the apertures from square lattice to triangle lattice to obtain a uniform resonance mode along the neighboring apertures. This leads to enhanced light transmission. The study gains understanding of new properties of the metamaterials based on plasmonic resonance.