Nonlocal study of ultimate plasmon hybridization

TL;DR

This paper investigates the fundamental limits of plasmon hybridization in nanometer-scale dimers using a nonlocal optical response model, revealing a fundamental hybridization limit at touching gaps and providing analytical resonance equations.

Contribution

It introduces a generalized nonlocal optical response model to analyze plasmon hybridization in dimers, deriving an analytical expression for resonance energies at touching gaps.

Findings

Identifies a fundamental limit on plasmon hybridization due to nonlocal effects.

Derives an analytical formula for resonance energies of touching dimers.

Shows the transition behavior from separated to overlapping dimers.

Abstract

Within our recently proposed generalized nonlocal optical response (GNOR) model, we revisit the fundamental problem of an optically excited plasmonic dimer. The dimer consists of two identical cylinders separated by a nanometre-sized gap. We consider the transition from separated dimers via touching dimers to finally overlapping dimers. In particular, we focus on the touching case, showing a fundamental limit on the hybridization of the bonding plasmon modes due to nonlocality. Using transformation optics we determine a simple analytical equation for the resonance energies of the bonding plasmon modes of the touching dimer.