Toroidal dipole associated resonant forward scattering of light by silicon nanoparticles

Abstract

In this work we investigate in terms of Cartesian multipoles the Kerker-type effect in high-index dielectric nanoparticles for which the third order multipoles give a considerable contribution to the light scattering process. We show that the Kerker-type effect can be associated with the resonant excitation of toroidal dipole moment (third order multipole) and, namely, with the interference of the scattered waves generated by electric, magnetic and toroidal dipole moments of high-index dielectric nanoparticles. From our theoretical results reveal, that the interplay between these moments with dominating contribution of toroidal dipole moment can provide strong suppression of the backward light scattering and, simultaneously, resonant forward light scattering.