Plasmonic Response of Nano-C-apertures: Polarization Dependent Field Enhancement and Circuit Model

The plasmonic response of C-shaped nano-apertures is investigated. Full-field numerical simulations are presented that show how the resonance condition depends on the wavelength and polarization of the incident light. Effects of dimension scaling are also discussed. A circuit model is proposed that relates geometrical and material parameters to equivalent inductive and capacitive circuit elements. The topological profile of the induced surface currents is used to find the representative inductance and capacitance values. The equivalent impedance of the circuit model is found to be correlated to the resonance behavior of the actual C-aperture. Comparison between the numerical simulations and the circuit model analysis shows agreement in predicting the resonant wavelength and bandwidth variations with C-aperture dimensions. The presented analysis can be useful in designing C-apertures for applications such as photonic metasurfaces, optical trapping, and fluorescence microscopy.

Automated summary

The plasmonic response of C-shaped nano-apertures is investigated in this study. Numerical simulations demonstrate the dependence of resonance condition on incident light wavelength and polarization. The effects of dimension scaling are also discussed. A circuit model is proposed, which relates geometrical and material parameters to equivalent circuit elements. The analysis finds correlation between the circuit model's equivalent impedance and the resonance behavior of actual C-apertures. The study's findings can be useful in designing C-apertures for various applications.