Optimum plasmon hybridization at percolation threshold of silver films near metallic surfaces

Abstract

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Optimum plasmon hybridization at percolation threshold of silver films near metallic surfaces AbstractWe demonstrate experimentally a strong interaction and, plasmonic hybridization from a nanosystem having both localized and delocalized surface plasmons modes simultaneously in the presence of a nearby thin continuous metallic film. In situ DC resistance measurement of silver films and percolation theory was used to determine accurately the systems where the percolation threshold exists by distinguishing the nucleation and growth regions of silver films. We found an optimum plasmon hybridization existing in this percolation threshold region which can be verified from the absorption spectra. We interpret our data in terms of a fitting of the absorption spectra to the Fano type line shapes model.

Long range plasmon assisted all-optical switching at telecommunication wavelengths

“…1(b) we show the effective index (left y-axis) n eff and the propagation distance (right y-axis) as a function of λ for a LRSP propagating along a d 10 nm uniform (no-grating) layer of silver embedded in As 2 S 3 . We remark that the use of the bulk dispersion [15] for the 10 nm Ag layer is justified by the experimental results available in literature [16][17]. We notice that the effective index of the LRSP is very close to the refractive index of the embedding material, As 2 S 3 in our case.…”

Modes of interaction between nanostructured metal and a conducting mirror as a function of separation and incident polarization

“…Such coupling can be strongly polarization dependent but this work and related theory indicates very close approach is needed, 10 to 12 nm for low index (n = 1.4 -1.5) spacers [10], and lower for higher index (n = 1.9 to 2.4) insulators. A study, which in common with this one, considered cross-coupling in the percolation zone did find an anomalously large absorptance, but attributed it to a Fano type coupling at a spacer thickness of 40 nm [11]. This is unlikely from reference [10], and this study clearly shows that at 40 nm amplification of absorption near percolation is due simply to phase modulation, and that STF's apply.…”

Plasmonic enhancement of second harmonic generation from nonlinear RbTiOPO_4 crystals by aggregates of silver nanostructures

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