Mie scattering of Laguerre-Gaussian beams: photonic nanojets and   near-field optical vortices
  We study Mie scattering of Laguerre-Gaussian (LG) light beams remodelled using the method of far-field matching. The theoretical results are used to analyze the optical field in the near-field region for purely azimuthal LG beams characterized by a nonzero azimuthal mode number $m_{LG}$. The mode number $m_{LG}$ is found to have a profound effect on the morphology of photonic nanojets and the near-field structure of optical vortices associated with the components of the electric field. 
Alexei D. Kiselev and Dmytro O. Plutenko
physics.optics