SPECTRAL ABSORPTION OF SILICON QUANTUM DOTS COUPLED TO SURFACE PLASMON MODES OF 𝐀𝐠 ⁄𝐒𝐢𝐎𝟐 CORE/SHELL NANOPARTICLES

Abstract In this thesis, we study theoretical and computational methods to investigate the effect of surface plasmon modes of Ag ⁄SiO2 core/shell nanoparticles on the spectral absorption of silicon quantum dot. The local field enhancement factor for the Ag ⁄SiO2 nanoparticles is solved using the Laplace equation. Utilizing this enhancement factor, the plasmon enhanced spectral absorption of silicon nanoparticle is studied and how the mean particle size, photon energy, metal fraction and composition of core/shell nanoparticles affect the absorption spectra of silicon nanoparticle. Our work presents a new approach for the local field enhancement factor mechanism of silicon nanocrystal by using phenomenological formulations that explain the mean particle, metal fraction and size dispersion affect the spectral absorption of silicon quantum dot. To investigate the mechanism of the local field enhancement factor we perform computer simulation using mathematic programming. These results show that, mean particle size, size dispersion and metal fraction increasing the spectral absorption as a function of photon energy of Silicon quantum dot also increase. Our results have in well agreement with many other theoretical and experimental findings. Our model confirms The Surface plasmon enhanced spectral absorption placed near to Ag ⁄SiO2 core/shell composite nanoparticles as a function of photon energy.