publications by Ashutosh Chilkoti.
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Papers Published
- Curry, A; Nusz, G; Chilkoti, A; Wax, A, Substrate effect on refractive index dependence of plasmon resonance for individual silver nanoparticles observed using darkfield microspectroscopy.,
Optics express, vol. 13 no. 7
(April, 2005),
pp. 2668-2677 [19495158], [doi] .
(last updated on 2025/04/18)Abstract:
We use optical darkfield micro-spectroscopy to characterize the plasmon resonance of individual silver nanoparticles in the presence of a substrate. The optical system permits multiple individual nanoparticles to be identified visually for simultaneous spectroscopic study. For silver particles bound to a silanated glass substrate, we observe changes in the Plasmon resonance due to induced variations in the local refractive index. The shifts in the plasmon resonance are investigated using a simple analytical theory in which the contributions from the substrate and environment are weighted with distance from the nanoparticle. The theory is compared with experimental results to determine a weighting factor which facilitates modeling of environmental refractive index changes using standard Mie code. Use of the optical system for characterizing nanoparticles attached to substrates for biosensing applications is discussed.Keywords:
Silver;Electron microscopy;Glass;Substrates;Refractive index;Biosensors;Codes (symbols);