Making a Conducting Metal with Optical Transparency via Coupled Plasmonic-Photonic Nanostructures

Abstract

Metallic film structures with simultaneous optical transparency and high electronic conductivity are of great importance for practical optoelectronic applications. Here, we predict a powerful scheme for transparent continuous metal film structure by using a plasmonic cylinder array and a high-index dielectric layer substrate. In the structure, the upper plasmonic crystal shows efficient optical field trapping of the incident light, acting as a light input coupler. The lower photonic layer provides a light release gate opening at the other side, acting as the light output coupler. The achieved broadband optical near-unity transparency (transmittance >94.5 %) originates from the dipole plasmon resonances of the plasmonic crystal, and the cavity resonances by the Fabry-Perot layer and their cooperative coupling effects. These findings could open a new and simplified alternative approach for highly transparent and conducting metal structures and hold potential applications in transparent conductors, filters, and ultracompact optoelectronic devices.