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Optical properties of microstructures based on metallic nanowires obtained by laser induced photochemistry
type: Distribution
access URL: https://theses.hal.science/tel-00845919
format: HTML
issued: 2026-05-10T07:31:23.802108
modified: 2026-05-10T07:31:23.767734

Optical properties of microstructures based on metallic nanowires obtained by laser induced photochemistry
type: Dataset
contact point: Organization
  fn: CCSD
keyword: optical-spectroscopy
keyword: nanostructures-metalliques
keyword: theses
keyword: metal-nanostructures
keyword: nanocharacterization
keyword: physcondcm-genphysics-physicscondensed-matter-cond-matother-cond-matother
keyword: infoeu-reposemanticsdoctoralthesis
keyword: spectroscopie-optique
keyword: nanocaracterisation
keyword: laser-nanostructuration
keyword: nanostructuration-laser
landing page: https://theses.hal.science/tel-00845919
description: We used a novel method of laser photochemistry to fabricate 3D microstructures based on metallic nanowires. Nanowires are obtained by laser photoreduction of metallic salt dissolved in a polymer matrix. The chemical reaction is initiated by the two-photon absorption of a photoreductor only at laser focal point. The geometry of microstructures is obtained by moving laser focal point according to suitable trajectories. In this thesis, we have studied the optical properties of of structures based on silver nanowires. A nanowire that stops a plane wave creates a diffracted field which shows parabolic trajectories of maxima and minima intensities. Calculations based on Rayleigh-Sommerfeld diffraction show that this typical figure corresponds to interferences between the incident plane wave and spherical waves generated at the two nanowire edges. When nanowires are arranged into set of parallel nanowires, spaced by a few microns, their diffracted fields generate intensity distributions similar to those of cylindrical refractive microlenses. In that case interference between the incident wave and the diffracted wave leads to a quadrative phase which is the at origin of focalisation. Manufacturing 2D arrays of nanowires allow to achieve very dense arrays of microlenses (10000x10000 DPI, dots per inch), which are impossible to make with refractive microlenses. The possibility to make 3D geometry permit to manipulate maxima and minima intensity trajectories for new diffractive functions at the microscopic scale. For instance manufacturing nanowires shifted in space leads to a new type of optical microdevice that allows the spatial separation of colors red, green and blue at microscopic scale.
identifier: NNT: 2012GRENY084
issued: 2026-05-10T07:31:23.779102
language: fr
modified: 2026-05-10T07:31:23.779107