Raman characterization of singlewalled carbon nanotubes and PMMA-nanotubes composites

The Raman spectroscopy have allowed us to perform studies on singlewalled nanotubes (SWNT's) produced by following methods: electric arc, laser ablation and solar energy. As this characterization method provides a great deal of informations, we will present a comparison between the nanotubes produced by all these processes and the influence of some synthesis parameters. By using spin casting, we have produced thin films of PMMA-SWNT's for different concentrations. Then, we have characterized these new materials by Raman spectroscopy. The aim of these investigations is to get information on the possible interactions between these two materials. In particular, we have studied the evolution of the composites films spectra as a function of the nanotubes concentration in the polymer.This work has been fully supported by the European Community through its Training and Mobility of Researcher program under network contract : NAMITECH, ERBFMRX- CT96-0067 @GlZ-MIHT) and by the tiench CNRS program : ULTIMATECH.Peer reviewe

Optical Nanoantennas for Multiband Surface-Enhanced Infrared and Raman Spectroscopy

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Light depolarization induced by sharp metallic tips and effects on Tip-Enhanced Raman Spectroscopy

1 - ArticleTip-Enhanced Raman Spectroscopy is based on the field enhancement and confinement provided by sharp metallic lips, used to locally excite the Raman emission from molecules, crystals and nanostructures. This technique has recently demonstrated capabilities for nanometer scale optical resolution in Raman analysis and has enormous potential applications in nano- and bio-technologies. In this paper we describe the state-of-the-art experimental techniques, focusing the attention oil the strategies to reduce the far-field background, on new processes to fabricate sharp metallic tips and on the effect of the depolarization produced by metallic tips on Tip-Enhanced Raman spectra of bulk crystals

Plasmonics: influence of the intermediate (or stick) layer on the efficiency of sensors

International audienceThe efficiency of plasmon-resonance-based sensors can be greatly improved with an accurate design of the nano-structures that constitute them. In this work we focus our attention on the design of a particular kind of these nanometric structures that consists of planar multilayered systems. We show the significant influence, on the plasmon resonance conditions, of the intermediate layer used to adhere a thin film of gold to a dielectric substrate. To illustrate this effect, we consider different intermediate layers to compute the optimal geometry that vanish the reflected energy. For this, we use the S-formulation and an evolutionary method for the electromagnetic and the optimization problems, respectively

Single wall carbon nanotubes: Two ways of production

International audienc

Raman characterization of singlewalled carbon nanotubes and PMMA-nanotubes composites

International audienc