Generation and focusing of a second-order vector beam using a subwavelength optical element

This article proposes a new type of subwavelength axicons for creating and focusing second-order vector cylindrical beams. It is also shown that using the proposed subwavelength axicons, it is possible to create focal spots with an energy backflow. The Comsol Multiphysics software is used to simulate the operation of subwavelength axicons with different twist angles. The dependence of the obtained intensity distributions on the angle of twist of the axicon spiral is investigated.