Multipolar third-harmonic generation driven by optically-induced magnetic resonances

TL;DR

This paper investigates third-harmonic generation in high-index dielectric nanoparticles, focusing on magnetic resonances and multipolar effects, to enable control of nonlinear optical emission at the nanoscale.

Contribution

It combines analytical and numerical methods to analyze nonlinear scattering near magnetic dipole resonances in simple nanoparticle geometries.

Findings

Revealed multipolar nature of third-harmonic fields near magnetic resonances

Demonstrated manipulation of nonlinear emission using all-dielectric nanostructures

Proposed designs for nonlinear optical antennas at the nanoscale

Abstract

We analyze third-harmonic generation from high-index dielectric nanoparticles and discuss the basic features and multipolar nature of the parametrically generated electromagnetic fields near the Mie-type optical resonances. By combining both analytical and numerical methods, we study the nonlinear scattering from simple nanoparticle geometries such as spheres and disks in the vicinity of the magnetic dipole resonance. We reveal the approaches for manipulating and directing the resonantly enhanced nonlinear emission with subwavelength all-dielectric structures that can be of a particular interest for novel designs of nonlinear optical antennas and engineering the magnetic optical nonlinear response at nanoscale.