Manipulation of the Pancharatnam phase in vectorial vortices

Opt Express. 2006 May 15;14(10):4208-20. doi: 10.1364/oe.14.004208.

Abstract

Linearly polarized vectorial vortices are analyzed according to their Pancharatnam phase and experimentally demonstrated using a geometric phase element consisting of space-variant subwavelength gratings. It is shown that in the absence of a Pancharatnam phase, stable vectorial vortices that have no angular momentum arise. In contrast, if a Pancharatnam phase is present the vectorial vortices have orbital angular momentum and collapse upon propagation.