https://doi.org/10.1007/s100530170091
Resonance and composition effects on the Raman scattering from silver-gold alloy clusters
1
Laboratoire de Physicochimie des Matériaux Luminescents, Université Lyon 1 and CNRS, 69622
Villeurbanne Cedex, France
2
Laboratoire de Spectrométrie Ionique et Moléculaire, Université Lyon 1 and CNRS, 69622
Villeurbanne Cedex, France
3
Département de Physique des Matériaux, Université Lyon 1 and CNRS, 69622 Villeurbanne Cedex,
France
Corresponding author: a portales@pcml.univ-lyon1.fr
Received:
16
November
2000
Published online: 15 September 2001
Low-frequency Raman scattering experiments have been performed on thin films consisting of pure gold or gold-silver alloy clusters embedded in alumina matrix. It is clearly shown that the quadrupolar vibrational modes are observed by Raman scattering because of the effect of resonance with the excitation of the electronic surface dipolar plasmon. This is due to the strong coupling between the collective electronic dipolar excitation and the quadrupolar vibrational modes. This effect of resonance does not exist with the core electron excitations. The mixing of the conduction electron dipolar excitation (surface plasmon) with the core electrons leads to the quenching of the resonant Raman scattering.
PACS: 36.40.Vz – Optical properties of clusters / 36.40.Gk – Plasma and collective effects in clusters / 78.30.Er – Solid metals and alloys / 36.20.Ng – Vibrational and rotational structure, infrared and Raman spectra / 73.61.At – Metal and metallic alloys
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001
