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Plasmonics

, Volume 1, Issue 1, pp 61–66 | Cite as

Drastic Surface Plasmon Mode Shifts in Gold Nanorods Due to Electron Charging

  • Paul MulvaneyEmail author
  • Jorge Pérez-Juste
  • Michael Giersig
  • Luis M. Liz-Marzán
  • Carlos Pecharromán
Original Paper

Abstract

The color of small gold rods changes dramatically when electrons are injected by chemical reductants. The longitudinal and transverse plasmon modes are both found to blue-shift, and the shift is larger for rods with larger aspect ratios. The color changes are visible to the eye for rods with aspect ratios around 2–3. It is found that the surface plasmon band is damped when charging becomes high. The effects are in qualitative agreement with a model in which the gold plasma frequency increases due to an increase in electron density.

Keywords

Gold rods Surface plasmon band Electron density Plasmon band shift Color changes 

Notes

Acknowledgments

P.M. wishes to thank the Humboldt Foundation for financial support and Stiftung Caesar. This work was supported through ARC Grant DP 0451651. LMLM acknowledges financial support from the Spanish Ministerio de Educación y Ciencia and FEDER (project # MAT2004-02991).

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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • Paul Mulvaney
    • 1
    • 2
    Email author
  • Jorge Pérez-Juste
    • 3
  • Michael Giersig
    • 1
  • Luis M. Liz-Marzán
    • 3
  • Carlos Pecharromán
    • 4
  1. 1.Nanoparticle Technology Group, Caesar StiftungBonnGermany
  2. 2.Chemistry SchoolUniversity of MelbourneParkvilleAustralia
  3. 3.Departamento de Química FísicaUniversidade de VigoVigoSpain
  4. 4.Instituto de Ciencia de Materiales de Madrid (CSIC)MadridSpain

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