Quantized evolution of the plasmonic response in a stretched nanorod

TL;DR

This study investigates how quantum effects, especially electron tunneling, cause discrete changes in the plasmonic response of a stretched nanorod, revealing quantum-induced discontinuities in the system's optical properties.

Contribution

It demonstrates, through first-principles calculations, the quantized evolution of plasmonic modes in a nanorod under stretching, highlighting the role of atomic-scale conduction channels.

Findings

Discontinuous changes in plasmonic response during stretching.

Correlation between conduction channels and plasmonic discontinuities.

Pronounced effects on charge-transfer plasmon intensity.

Abstract

Quantum aspects, such as electron tunneling between closely separated metallic nanoparticles, are crucial for understanding the plasmonic response of nanoscale systems. We explore quantum effects on the response of the conductively coupled metallic nanoparticle dimer. This is realized by stretching a nanorod, which leads to the formation of a narrowing atomic contact between the two nanorod ends. Based on first-principles time-dependent density-functional-theory calculations, we find a discontinuous evolution of the plasmonic response as the nanorod is stretched. This is especially pronounced for the intensity of the main charge-transfer plasmon mode. We show the correlation between the observed discontinuities and the discrete nature of the conduction channels supported by the formed atomic-sized junction.