Optical response of single silver nano-objects : plasmonic coupling and photo-oxidation
type: Dataset
description: The optical properties of noble metal nanoparticles are known to be dominated by the localized surface plasmon resonance (SPR) which is highly sensitive to the size of the particles, their shape, their environment, and eventually their chemical composition in the case of mixed systems. In order to study the optical response of a single supported metallic nanoparticle, a high sensitive spectroscopic setup using a white lamp (300-900 nm) has been developed in a transmission measurement configuration. This technique, the Spatial Modulation Spectroscopy, aims to detect the overall extinction of light by a nanoparticle. Moreover, the coupling of this technique with the direct observation of the particles by Transmission Electron Microscopy allows to get an unambiguous description of their optical response in relation with their exact morphology. In this work, the optical response of single silver nano-objects has been correlated with their morphology and their structure at a sub-nanometer scale. Time evolution of the optical response of single silver nanocubes under illumination was first investigated. We observed a “spherization” and a photo-oxidation due to the UV part of the light. Moreover, we studied pairs of cubic silver nanoantennas that showed a huge sensitivity of their optical response with the interparticle distance and their morphology. Indeed, the SPR is red-shifted with decreasing interparticle distance. One can also observe a striking splitting of the resonance for very low interparticle distances. Preliminary DDA calculations seem to show that the radius of curvature at the corners and edges of both cubes plays a key role in the splitting of the resonance
identifier: NNT: 2011LYO10135
issued: 2026-05-10T07:43:08.317333
language: fr
modified: 2026-05-10T07:43:08.317338
contact point: Organization
  fn: CCSD
keyword: couplage-plasmonique
keyword: effets-de-forme
keyword: infoeu-reposemanticsdoctoralthesis
keyword: metaux-nobles
keyword: nanoparticules-uniques
keyword: noble-metal
keyword: optical-properties
keyword: photo-oxidation
keyword: photo-oxydation
keyword: physcondcm-genphysics-physicscondensed-matter-cond-matother-cond-matother
keyword: plasmonic-coupling
keyword: proprietes-optiques
keyword: shape-effects
keyword: single-nanoparticle
keyword: theses
landing page: https://theses.hal.science/tel-00728160

Optical response of single silver nano-objects : plasmonic coupling and photo-oxidation
type: Distribution
format: HTML
issued: 2026-05-10T07:43:08.340239
modified: 2026-05-10T07:43:08.300395
access URL: https://theses.hal.science/tel-00728160

test_moissonnage_selune
type: Agent