An analytical solution for light scattering by metallic cylindrical nanoparticles with core–shell structure

Abstract

In this paper, the optical scattering from cylindrical plasmonic nanoparticles with a core–shell structure, while the core is dielectric coated by a metallic shell such as gold, is investigated by using an analytical solution in the framework of Mie theory. A closed-form (CF) formalism that determines the optical properties of cylindrical nanoparticles based on the series expansions of Bessel functions for the Mie scattering coefficients is introduced and presented. By using this formulation, we will show the optical response and the surface plasmon resonance of hybrid metal-based nanoparticles with cylindrical shape is dependent on the radius of nanoparticle, the refractive index of core and physical environment of nanoparticle. Also, the influence of interband transitions on the optical scattering by plasmonic nanoparticles is discussed and interpreted using the Drude–Lorentz model because the optical properties of metals arise from both the optical excitation of interband transitions and the free electron response.