Local transfer of optical angular momentum to matter

In this paper, the problem of the local and global features of the angular momentum of light in a consistent treatment of the interaction with dielectric objects is resolved. This process is modelled with a simple ansatz describing the field after the object, in the limits of a paraxial light beam and of a weak dielectric (refractive index ∼1), describing effects as absorption, action of spiral phase plates, as well as birefringence. The transferred angular momentum is then calculated.