  High-index spherical nanoparticles with low material losses support sharp
high-Q electric and magnetic resonances and exhibit a number of interesting
optical phenomena. Developments in fabrication techniques have enabled the
further study of their properties and the investigation of related optical
effects. After deposition on a substrate, the optical properties of a particle
change dramatically due to mutual interaction. Here, we consider a silicon
spherical nanoparticle on a dielectric one-layered substrate. At the normal
incidence of light, the layer thickness controls the contribution of the
nanoparticle's electric and magnetic multipoles to the subsequent optical
response. We show that changing the polarization of incident light at a
specific excitation angle and layer thickness leads to switching between the
multipoles. We further observe a related polarization-driven control over the
direction of the scattered radiation.
