Observation of intrinsic size effects in the optical response of individual gold nanoparticles

Stéphane Berciaud (1) , Laurent Cognet (1) , Philippe Tamarat (1) , Brahim Lounis (1)

1 CPMOH - Centre de physique moléculaire optique et hertzienne

The Photothermal Heterodyne Imaging method is used to study for the first time the absorption spectra of individual gold nanoparticles with diameters down to 5 nm. Intrinsic size effects wich result in a broadening of the Surface Plasmon resonance are unambiguously observed. Dispersions in the peak energies and homogeneous widths of the single particle resonances are revealed. The experimental results are analysed within the frame of Mie theory.

Mots clés: gold nanoparticle; single particle detection; absorption spectroscopy; Mie; intrinsic effect

Domaines: Optique [physics.optics]; Autre [cond-mat.other]

Stéphane Berciaud, Laurent Cognet, Philippe Tamarat, Brahim Lounis. Observation of intrinsic size effects in the optical response of individual gold nanoparticles. Nano Letters, 2005, 5 (3), pp.515. ⟨10.1021/nl050062t⟩. ⟨hal-00143957v2⟩