Polarization ellipse strips in nonparaxial optical fields (brief review)

This is a brief review of five-year studies of features of nontrivial three-dimensional topological structures of the electromagnetic field–optical strips–formed by vectors characterizing the sizes and orientation of the polarization ellipse of the light field with tracing of change in the orientations of these vectors along closed contours of various shapes, which are linked to lines of polarization singularity or are located immediately near them. The characteristics of polarization strips formed on arbitrarily oriented small circular contours around a single circular polarization singularity line of the electromagnetic field are described. The topology of polarization strips of light scattered by a dielectric sphere and a metallic spheroid with subwavelength sizes when elliptically polarized harmonic plane waves are incident on them is discussed. Optical polarization strips existing in the focal region of a parabolic mirror that tightly focus various laser beams incident on it is described. The topology of polarization ellipse strips in the electromagnetic field of laser radiation propagating in a planar metamaterial is discussed.