Multi-faceted plasmonic nanocavities

TL;DR

This paper investigates the complex optical behaviors of plasmonic nanocavities formed by polyhedral nanoparticles, revealing insights into energy coupling and control of light-matter interactions for applications like photocatalysis.

Contribution

It introduces a detailed analysis of nanocavities made from polyhedral nanoparticles and demonstrates a recombination technique to study their far-field optical responses.

Findings

Rich optical behavior in near- and far-field modes

Energy coupling mechanisms within nanocavities elucidated

Potential for controlling photocatalytic reactions

Abstract

Plasmonic nanocavities form very robust sub-nanometer gaps between nanometallic structures and confine light in deep subwavelength volumes to enable unprecedented control on light-matter interactions. However, spherical nanoparticles acquire various polyhedral shapes during their synthesis, which has defining impact on controlling many light-matter interactions, such as photocatalytic reactions. Here, we focus on nanocavities made of three polyhedral nanoparticles (cuboctahedron, rhombicuboctahedron, decahedron) that commonly occur during the synthesis of spherical nanoparticles. Their photonic modes have a very intricate and rich optical behaviour, both in the near- and far-field. Through a recombination technique, we obtain the total far-field produced by a molecule placed within these nanocavities, to reveal how energy couples in and out of the system. This work paves the way towards understanding and controlling light-matter interactions, such as photocatalytic reactions and non-linear vibrational pumping, in such extreme environments.