Variations arising in extinction spectra of nanoparticle aggregates upon deformation during deposition on planar dielectric substrate

摘要

Variations in the extinction spectra of aggregates of plasmon-resonant nanoparticles are studied at different stages of their planar deformation during interaction with dielectric substrates. Deformation and extinction spectra are calculated by the Brownian dynamics and coupled dipole methods, respectively. The effect of planar deformation of the aggregates on the pattern of the extinction contour in the range of the plasmon absorption band is analyzed by the example of aggregated silver hydrosols. It is shown that the extinction spectra of three-dimensional nanoparticle aggregates formed in bulk and those deformed upon deposition onto a substrate are markedly different. The calculation results are confirmed by experimental data.