Tailoring the excitation of localized surface plasmon-polariton resonances by focusing radially-polarized beams

TL;DR

This paper investigates how focused radially-polarized beams can selectively excite localized surface plasmon-polariton resonances in metal nanospheres, offering enhanced control over optical responses for nano-optics applications.

Contribution

It introduces a multipole expansion approach to analyze the interaction and demonstrates the superior tuning capabilities of radially-polarized beams over traditional light sources.

Findings

Radially-polarized beams enable better control of plasmonic resonances.

Enhanced near- and far-field tuning with focused radially-polarized light.

Potential applications in nano-optics and optical data storage.

Abstract

We study the interaction of focused radially-polarized light with metal nanospheres. By expanding the electromagnetic field in terms of multipoles, we gain insight on the excitation of localized surface plasmon-polariton resonances in the nanoparticle. We show that focused radially-polarized beams offer more opportunities than a focused plane wave or a Gaussian beam for tuning the near- and far-field system response. These results find applications in nano-optics, optical tweezers, and optical data storage.