Influence of spatial dispersion in metals on the optical characteristics of bimetallic plasmonic nanoparticles

The problem of diffraction of an electromagnetic plane wave field on a core-shell nanoparticle composed of two plasmon metals is considered. The effect of spatial dispersion in metals on the absorption cross section is investigated on the basis of the Discrete Sources method. Various combinations of core and shell metals: Au@Ag and Ag@Au of spheroidal particles, as well as the effect of elongation and asymmetry of particle geometry on energy absorption are being studied. It was found that taking into account the spatial dispersion, both in the core and in the shell, leads to a significant decrease in the absorption cross section and a shift of the plasmon resonance to the shorter wavelength region.