Nature of the Poynting Vector Field Singularities in Resonant Light Scattering by Nanoparticles

Singularities of the Poynting vector field subwavelength patterns in resonant light scattering by nanoparticles are discussed and classified. There are two generic types of the singularities, namely, (i) the singularities related to the vanishing of the magnetic (and/or electric) field at the singular points and (ii) the singularities related to the formation of standing waves in proximity to the singular points. The connection of these types of singularities to the topology of the singular points, space dimension (3D vs. 2D), and energy conservation law are revealed. In particular, it is shown that in 2D cases in non-dissipative media, the energy conservation reduces the possible types of generic singular points to saddles and centers only. In 3D cases, a universal expression connecting different components of the Poynting vector and valid for any generic singularities is derived and numerically checked for various types of singular points.

Automated summary

This paper discusses and categorizes the singularities of the Poynting vector field in subwavelength patterns in resonant light scattering by nanoparticles. There are two generic types of singularities, one related to the vanishing of the magnetic (and/or electric) field at the singular points, and the other related to the formation of standing waves in proximity to the singular points. The paper reveals the connection of these singularities to the topology of the singular points, space dimension (3D vs. 2D), and energy conservation law.