Plasmonics: Absorption and scattering of light of non-straight ordered array of Au rings

In this paper, Au nanorings in a SiO₂ substrate have been utilized to design a plasmonic waveguide with lower losses and perfect energy coupling. Our recommended structure consists of a chain of dozen Au nanorings with a given intercenter space between them going on resonance, if a beam with specific wavelength is launched in the input area of the waveguide. Nanoring has an extra degree of freedom in its geometry and have a preferable tunability in comparison to other shapes of nanoparticles (e.g. nanospheres). It is shown that a modified plasmon waveguide structure can be utilized at optical communication band (λ = 1550 nm), in optical integrated devices. Red-shifted of localized surface plasmon resonance (LSPR) has been considered as a fundamental condition to have a maximum of optical response at λ = 1550 nm. Cross-sectional depictions of field propagation through the structure are displayed in order to show the absorption and scattering of light by particles. Ultimately, transmitted power ratio is computed for the structure to clear-cutting its characteristics.