Optical Hall Effect at the Tight Focus of Hybrid Vector Beams

Using the Richards-Wolf equations, the focusing of circularly polarized light by plane diffractive lenses is theoretically considered. It is shown that at the focus of a circularly polarized optical beam, circular regions of different radii are formed with a center on the optical axis with alternating directions of rotation of the polarization vector (clockwise and counterclockwise). This radius-dependent separation of oppositely directed "spins" is a manifestation of the radial spin Hall effect at the focus. Potential applications are as follows: the flat top focus can find use in microscopy to obtain a uniform field of view, while the radial rotation Hall effect can be used to position absorbing microparticles in the opposite position.