Fano-like interference of plasmon resonances at a single rod-shaped nanoantenna

TL;DR

This paper explains the asymmetric scattering spectra of single metallic nanorods as Fano-like interference between overlapping plasmon resonances, supported by analytical and numerical analysis.

Contribution

It introduces a new understanding of plasmon resonance interactions in single nanoantennas through Fano interference, combining analytical and numerical methods.

Findings

Fano-like interference explains asymmetric spectra

Resonances overlap spatially and in frequency for Fano effects

Analytical and numerical results support the model

Abstract

Single metallic nanorods acting as half-wave antennas in the optical range exhibit an asymmetric, multi-resonant scattering spectrum that strongly depends on both their length and dielectric properties. Here we show that such spectral features can be easily understood in terms of Fano-like interference between adjacent plasmon resonances. On the basis of analytical and numerical results for different geometries, we demonstrate that Fano resonances may appear for such single-particle nanoantennas provided that interacting resonances overlap in both spatial and frequency domains.