Strong coupling between a metallic nanoparticle and a single molecule

TL;DR

This paper develops a quantum-mechanical theory to demonstrate that strong coupling between a single molecule and a metallic nanoparticle can occur, leading to observable spectral splitting in fluorescence.

Contribution

It introduces a combined Drude and boundary-element-method approach to model the quantum interaction between molecules and metallic nanoparticles.

Findings

Strong coupling is theoretically possible between a single molecule and nanoparticle.

Coupling results in observable splitting of emission peaks in fluorescence spectra.

The developed model accurately describes surface plasmon polaritons and their interaction with molecules.

Abstract

We theoretically investigate strong coupling between a single molecule and a single metallic nanoparticle. A theory suited for the quantum-mechanical description of surface plasmon polaritons (SPPs) is developed. The coupling between these SPPs and a single molecule, and the modified molecular dynamics in presence of the nanoparticle are described within a combined Drude and boundary-element-method approach. Our results show that strong coupling is possible for single molecules and metallic nanoparticles, and can be observed in fluorescence spectroscopy through the splitting of emission peaks.