Lefrant, S., Buisson, J.-P., Mevellec, J.-Y., Baltog, I. & Baibarac, M. (2008) Single-beam pumped coherent anti-Stokes Raman scattering on carbon nanotubes. Phys. Status Solidi B-Basic Solid State Phys. 245 2221–2224.
Added by: Laurent Cournède (2016-03-10 21:58:41)
|Type de référence: Article
Numéro d'identification (ISBN etc.): 0370-1972
Clé BibTeX: Lefrant2008
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Créateurs: Baibarac, Baltog, Buisson, Lefrant, Mevellec
Collection: Phys. Status Solidi B-Basic Solid State Phys.
Consultations : 2/771
Indice de consultation : 3%
Indice de popularité : 0.75%
Giant optical fields locally generated in nanoscale metal structures through the local excitation of surface plasmons underlie a variety of nonlinear optical processes. Using silver and gold rough metallic films, reproducible enhancements of the Raman signal on various materials including carbon nano-tubes have been demonstrated. In addition, an abnormal anti-Stokes Raman emission, reminiscent of Coherent anti-Stokes Raman Scattering (CARS), is accurately observed on nano-metric thin films. We demonstrate that under a tight focusing of the excitation light, a CARS-type emission, resulting from a wave mixing process between the incident laser light and Stokes Raman light generated by a SERS mechanism, is produced. The results which corroborate the CARS emission are the following: a square relation between the CARS signal intensity and the film thickness; a square relationship between the CARS signal intensity and the exciting laser intensity; a dependence of the CARS intensity on the numerical aperture (NA) of the microscope objective used for the detection of the anti-Stokes signal; a polarization ratio in the anti-Stokes side always greater in comparison with that measured for an usual Stokes Raman signal. We demonstrate also that this mechanism may contribute to a clear identification of the state of the observed nanotubes, i.e. in isolated or bundled forms, even when tubes are in powders. (C) 2008 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim
Added by: Laurent Cournède