Polarization-independent Fano resonances in arrays of core-shell nanoparticles

Abstract

We study the scattering properties of arrays of core-shell nanoparticles and reveal the existence of polarization-independent Fano resonances. Such Fano resonances occur through the interaction of a pair of degenerate orthogonal electric and artificial magnetic modes of the same strength with the spectrally narrow geometric resonance due to the diffractive coupling in the array. Furthermore, we show that for different polarizations of the incident plane waves, the electric and magnetic modes supported by each nanoparticle can be selectively controlled, providing extra freedom for near-field manipulation, with applications to nonlinear and lasing devices.