Characterization of core-shell nanostructure consisting Si-Au-SiO_2 based on manipulation of optical properties

摘要

In this article, we investigated some physical characteristics of core-shell nanostructure in optical regime and perturbation has been also introduced as an effective method in shaping of optical properties. The proposed nanostructures are composed of the selected materials as: Silicon, Silicon Dioxide and Gold. At first, the extinction cross section spectra are calculated for multilayer core-shell nanostructures in optical range and the configuration effect of the constructed materials in a multilayer nanostructure are investigated for determination of Plasmon range. Then, the new structures of core-shell nanoparticles (gold-silicon) are presented, which have an amount of impurity particle in their shells as perturbation and also their extinction cross section spectra are calculated. The obtained results in this article give a proper approach about perturbation effect in broadening, sharpening and shifting of optical response which are decisive factors especially nano-network systems. Indeed, it has been proposed that the impurity particles in the shells can be a mechanism for tuning of optical characteristics of the presented nanoparticles in practical fields and also creation of local oscillations as plasmonic resonances in a considered optical range. Besides, redshift in extinction cross section can be also created by particle perturbation. At the end, the effective permittivity of the perturbed core-shells are extracted. The optional frequency range is selected between 300 and 900 (THz).