A classical picture of subnanometer junctions: an atomistic Drude approach to nanoplasmonics

TL;DR

This paper introduces a novel classical atomistic approach called {Q} for modeling the optical properties of subnanometer metal junctions, accurately capturing quantum effects like tunneling and plasmonic behavior.

Contribution

The paper presents a new classical atomistic model that effectively reproduces quantum nanoplasmonic phenomena in subnanometer junctions, bridging classical and quantum descriptions.

Findings

{Q} accurately reproduces ab initio plasmonic behavior.

Classical atomistic approach can describe quantum-dominated nanoplasmonics.

Potential for large-scale nanoplasmonic simulations.

Abstract

The description of optical properties of subnanometer junctions is particularly challenging. Purely classical approaches fail, because the quantum nature of electrons needs to be considered. Here we report on a novel classical fully atomistic approach, {\omega}FQ, based on the Drude model for conduction in metals, classical electrostatics and quantum tunneling. We show that {\omega}FQ is able to reproduce the plasmonic behavior of complex metal subnanometer junctions with quantitative fidelity to full ab initio calculations. Besides the practical potentialities of our approach for large scale nanoplasmonic simulations, we show that a classical approach, in which the atomistic discretization of matter is properly accounted for, can accurately describe the nanoplasmonics phenomena dominated by quantum effects.