Light scattering by a thin wire with a surface-plasmon resonance: Bifurcations of the Poynting vector field

We analyze the energy flow during the scattering of a plane wave by a small homogeneous cylinder in the vicinity of surface-plasmon resonance, where ${\epsilon }^{\prime }=\mathrm{Re}\epsilon =-1$ ($\epsilon$ stands for permittivity). For the case of small dissipation, ${\epsilon }^{″}=\mathrm{Im}\epsilon <<1$, this scattering can strongly deviate from the classical dipole approximation (Rayleigh scattering). In certain specified cases, the Rayleigh scattering is replaced with an anomalous light scattering regardless the wire smallness. The phenomenon is based on interplay of the usual dissipative and radiative damping, where the latter is related to inverse transformation of localized resonant plasmons into scattered light. The anomalous light scattering possesses a variety of unusual features, such as an inverse hierarchy of optical resonances and a complicated near-field structure, which may include optical vortexes, optical whirlpools, and other peculiarities in nanoscale area.