Gold nanoparticle assemblies: interplay between thermal effects and optical response

Abstract

The optical response of materials based on gold nanoparticle assemblies depends on many parameters regarding both material morphology and light excitation characteristics. In this paper, the interplay between the optical and thermal responses of such media is particularly investigated under its theoretical aspect. Both conventional and original modeling approaches are presented and applied to concrete cases. We first show how the interaction of light with matrix-embedded gold nanoparticles can result in the generation of thermal excitations through different energy exchange mechanisms. We then describe how thermal processes can affect the optical response of a nanoparticle assembly. Finally, we connect both aspects and point out their involvement in the nonlinear optical response of nanocomposite media. This allows us to tackle two key issues in the field of third-order nonlinear properties of gold nanoparticles: The influence of the generalized thermal lens in the long laser pulse regime and the hot electron contribution to the gold particle intrinsic third-order susceptibility, including its spectral dispersion and intensity-dependence. Additionally, we demonstrate the possible significant influence of the heat carrier ballistic regime and phonon rarefaction in the cooling dynamics of an embedded gold nanoparticle subsequent to ultrafast pulsed laser excitation.

Ultrasmall all-optical plasmonic switch and its application to superresolution imaging

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Plasmon drag effect in metal nanostructures

“…This simple approximation can describe both the polarity and magnitude of the induced emf. However, it cannot fully present the physical picture, taking into account that the estimated width of the positively charged layer, h, is less or on the order of the lattice constant, l. Alternative models can be based on the consideration of hot electron excitation and emission [27] or thermal effects [28] that may also exhibit such an asymmetry depending on the boundary conditions.…”

Understanding the photothermal heating effect in non-lamellar liquid crystalline systems, and the design of new mixed lipid systems for photothermal on-demand drug delivery

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