|approved||summary_crut.pdf||2015-03-27 07:48:49||Aurélien Crut|
Author: Aurélien Crut
Requested Type: Pre-Selected Invited
Submitted: 2015-03-13 08:22:10
Co-authors: A. Lombardi, E. Pertreux, V. Juvé, P. Maioli, F. Vallée, N. Del Fatti
FemtoNanoOptics group, Institut Lumière Matière
10, rue Ada Byron
Understanding and modeling the optical response of nano-objects is currently an active field of research, which has greatly benefited from the development of experimental methods enabling optical spectroscopy of individual nanoparticles. In particular, the polarization-resolved extinction spectrum of a single nano-object can be quantitatively measured by “spatial modulation spectroscopy” and compared to simulations based on its actual morphology, determined either optically or using 2D and 3D electron microscopy.
In this talk, we will discuss the effects of the size, shape and local environment of substrate-deposited elongated nano-objects on the properties of their localized surface plasmon resonance (SPR). In the case of silica-coated gold nanorods, isolation from the substrate provided by the silica shell largely reduces interaction with the environment, allowing quantitative investigation of quantum confinement effects, which manifest as a size-dependent SPR broadening. Conversely, deposition on transparent or absorbing substrates has a large impact for bare gold nano-objects (such as nanorods or bipyramids), inducing a shift and, for absorbing substrates, broadening of SPR. Numerical simulations and correlation of the optical experiments with morphological characterizations of the nano-objects by electron tomography demonstrate the large importance of the particle-substrate distance and 3D nano-object orientation.