  We study the scattering of infrared light by small dielectric core-shell
particles taking a sapphire sphere with a CaO core as an example. The
extinction efficiency of such a particle shows two intense series of resonances
attached, respectively, to in-phase and out-of-phase multipolar
polarization-induced surface charges build-up, respectively, at the core-shell
and the shell-vacuum interface. Both series, the character of the former may be
labelled bonding and the character of the latter antibonding, give rise to
anomalous scattering. For a given particle radius and filling factor the
Poynting vector field shows therefore around two wave numbers the complex
topology of this type of light scattering. Inside the particle the topology
depends on the character of the resonance. The dissipation of energy inside the
particle also reflects the core-shell structure. It depends on the resonance
and shows strong spatial variations.

Mesoscale and Nanoscale Physics;Optics