The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics

, Volume 20, Issue 2, pp 251–260

Optical properties of silver clusters formed by ion irradiation

Authors

  • J.C. Pivin
    • Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse, bâtiment 108, 91405 Orsay Campus, France
  • M.A. García
    • Departamento de Física de Materiales, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
  • H. Hofmeister
    • Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle, Germany
  • A. Martucci
    • Dipartimento di Ingegneria Meccanica, Universita di Padova, via Marzolo 9, 35131 Padova, Italy
  • M. Sendova Vassileva
    • Central Laboratory for Solar Energy and New Energy Sources, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee blvd., 1784 Sofia, Bulgaria
  • M. Nikolaeva
    • Central Laboratory for Solar Energy and New Energy Sources, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee blvd., 1784 Sofia, Bulgaria
  • O. Kaitasov
    • Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse, bâtiment 108, 91405 Orsay Campus, France
  • J. Llopis
    • Departamento de Física de Materiales, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid, Spain

DOI: 10.1140/epjd/e2002-00130-3

Cite this article as:
Pivin, J., García, M., Hofmeister, H. et al. Eur. Phys. J. D (2002) 20: 251. doi:10.1140/epjd/e2002-00130-3

Abstract:

Precipitation of silver clusters in silica is achieved by different methods: ion implantation, ion beam mixing of superimposed layers and ion irradiation of films deposited by means of co-sputtering or sol-gel technique. Main features of the nanoparticles depending on the preparation method are investigated by TEM. The optical extinction resonance of these clusters is analysed in terms of sizes and interaction between the clusters on the basis of calculations. We found that resonances in sputtered and gel films with low metal concentrations are well described by plasmon polaritons in isolated clusters and calculations based on Mie theory allow the study of their growth under irradiation. This theory is not appropriate to describe the optical response of silver clusters in silica implanted with Ag concentrations higher than 5 at.% or in ion beam mixed films, because of the interaction between clusters. Using an effective medium model, it is demonstrated that the random dispersion of clusters in implantation films causes fluctuations and, on average, an increase of the clusters polarization. On the contrary, the particular arrangement of the clusters with a bimodal size distribution in ion beam mixed films induces a screening effect between the clusters of largest size.

PACS. 61.46.+w Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals – 78.40.-q Absorption and reflection spectra: visible and ultraviolet

Copyright information

© EDP Sciences, Springer-Verlag, Società Italiana di Fisica 2002