Exotic Grazing Resonances in Nanowires

TL;DR

This paper uncovers a new family of grazing resonances in nanowires that exhibit higher Q factors, broader bandwidths, and less susceptibility to material losses, applicable to both dielectric and metallic nanowires.

Contribution

It introduces and explains the existence of exotic grazing resonances in nanowires, expanding understanding beyond traditional surface plasmon resonances.

Findings

Grazing resonances have higher Q factors and broader bandwidths.

These resonances are less affected by material losses.

They can be excited in both dielectric and metallic nanowires regardless of polarization.

Abstract

We investigate electromagnetic scattering from nanoscale wires and reveal for the first time, the emergence of a family of exotic resonances, or enhanced fields, for source waves close to grazing incidence. These grazing resonances can have a much higher Q factor, broader bandwidth, and are much less susceptible to material losses than the well known surface plasmon resonances found in metal nanowires. Contrary to surface plasmon resonances however, these grazing resonances can be excited in both dielectric and metallic nanowires and are insensitive to the polarization state of the incident wave. This peculiar resonance effect originates from the excitation of long range guided surface waves through the interplay of coherently scattered continuum modes coupled with the azimuthal first order propagating mode of the cylindrical nanowire. The nanowire resonance phenomenon revealed here can be utilized in broad scientific areas, including: metamaterial designs, nanophotonic integration, nanoantennas, and nanosensors.