Tunable magneto-optical linear and circular dichroism spectra for a dimer of core–shell prolate spheroids

Abstract

Searching for methods to modulate localized surface plasmons in nanoparticles is one of the challenging and important areas in plasmonic effects. Surface plasmons can be influenced in a magnetic field due to the additional magnetic force on the electrons, resulting in some magneto-optical phenomena. In this paper, we study the magneto-optical properties of core–shell spheroidal nanoparticles. We apply the coupled dipole method to calculate the absorption and linear and circular dichroism spectra of a single nanoparticle and a dimer of nanoparticles. The polarizability tensor of spherical nanoparticles is extended for spheroidal nanoparticles, and, by utilizing it, we show that the single spheroidal nanoparticle reveals circular dichroism. It is reported that core size and nanoparticles axis direction can be used to engineer the whole spectrum for both configurations.