Multipole plasmons and their disappearance in few-nanometre silver nanoparticles

Søren Raza, Shima Kadkhodazadeh, Thomas Christensen, Marcel Di Vece, Martijn Wubs, N. Asger Mortensen, Nicolas Stenger

Research output: Contribution to journalJournal articleResearchpeer-review

419 Downloads (Pure)

Abstract

Electron energy-loss spectroscopy can be used for detailed spatial and spectral characterization of optical excitations in metal nanoparticles. In previous electron energy-loss experiments on silver nanoparticles with radii smaller than 20 nm, only the dipolar surface plasmon resonance was assumed to play a role. Here, applying electron energy-loss spectroscopy to individual silver nanoparticles encapsulated in silicon nitride, we observe besides the usual dipole resonance an additional surface plasmon resonance corresponding to higher angular momenta for nanoparticle radii as small as 4 nm. We study the radius and electron beam impact position dependence of both resonances separately. For particles smaller than 4 nm in radius the higher-order surface plasmon mode disappears, in agreement with generalized non-local optical response theory, while the dipole resonance blueshift exceeds our theoretical predictions. Unlike in optical spectra, multipole surface plasmons are important in electron energy-loss spectra even of ultrasmall metallic nanoparticles.
Original languageEnglish
Article number8788
JournalNature Communications
Volume6
Number of pages9
ISSN2041-1723
DOIs
Publication statusPublished - 2015

Bibliographical note

This work is licensed under a Creative Commons Attribution 4.0 International License.

Fingerprint

Dive into the research topics of 'Multipole plasmons and their disappearance in few-nanometre silver nanoparticles'. Together they form a unique fingerprint.

Cite this