Electromagnetic response of broken-symmetry nano-scale clusters

TL;DR

This paper develops a microscopic response theory to model electromagnetic interactions with nano-scale clusters, revealing the limitations of classical Mie theory at small scales where molecular excitations dominate.

Contribution

It introduces a non-local response model that captures the transition from plasmon resonances to molecular excitations in nano-scale clusters.

Findings

Classical Mie theory breaks down at small scales.

Molecular excitations replace plasmon resonances below a critical threshold.

Spectral intensity of resonances is suppressed at nano-scale.

Abstract

A microscopic, non-local response theory is developed to model the interaction of electromagnetic radiation with inhomogeneous nano-scale clusters. The breakdown of classical continuum-field Mie theory is demonstrated at a critical coarse-graining threshold, below which macroscopic plasmon resonances are replaced by molecular excitations with suppressed spectral intensity.