Experimental Demonstration of Diffraction of Vector Field Singularities Through Diamond Shaped Aperture

摘要

We investigate the peculiar diffraction behavior of the vector fields on passing through a diamond shaped aperture. The higher-order vector fields embedded with V-point singularity are generated using a rectangular path Sagnac interferometer. It is witnessed that the order (magnitude of Poincare-Hopf index) of the vector field singularity can be directly predicted by counting the number of intensity nulls of the diffraction pattern. The method of diffraction and polarization transformations reported here can be used to generate variety of on-axis and off-axis polarization singular beams, beams with multiple polarization singularities, full Poincare' beams etc.