Poynting Vector Behavior of Cylindrical Vector Beam Focused by Gradient Index Lens

摘要

In this paper, we investigated the focusing of a second-order cylindrical vector beam by a gradient index lens. It was shown that the lens forms a region of the reverse energy flow near its shadow surface. If the lens length is made with a spherical hole on the axis, it is possible to localize the region of the direct energy flow inside the lens material, and the region with the reverse energy flow into free space.