Mode-balancing far field control of light localization in nanoantennas

TL;DR

This paper demonstrates how tuning the incident light's orientation can control light localization in nanoantennas, enabling enhanced near-field intensities and optical transparency at a subwavelength scale.

Contribution

It introduces a method to control light localization in nanoantennas via mode-balancing, achieving near-field enhancement and transparency through simple incident wave tuning.

Findings

Symmetric and antisymmetric mode-balancing enhances near-field intensity.

Dipolar moment can be fully extinguished in coupled nanoparticle systems.

Optical transparency achieved in ultra-compact metallic structures.

Abstract

Light localization is controlled at a scale of lambda/10 in the harmonic regime from the far field domain in a plasmonic nanoantenna. The nanoantenna under study consists of 3 aligned spheres 50 nm in diameter separated by a distance of 5 nm. By simply tuning the orientation of an incident plane wave, symmetric and antisymmetric mode-balancing induces a strong enhancement of the near field intensity in one cavity while nullifying the light intensity in the other cavity. Furthermore, it is demonstrated that the dipolar moment of a plasmonic particle can be fully extinguished when strongly coupled with a dimer of identical nanoparticles. Consequently, optical transparency can be achieved in an ultra-compact symmetric metallic structure.