Abruptly autofocusing polycyclic tornado ring Airy beam

Abstract

We introduce numerically a new polycyclic tornado ring Airy beam (PTRAB) induced by annular spiral zone phases with the second order chirped factor. The PTRAB has such properties of controllable multi focuses, the multi optical bottles and rotation. By choosing appropriate parameters, we can control the times of the multi autofocus and the autofocusing distance, the size and the number of the OBs, the quantity of the spots and the location where the rotary direction changes from counterclockwise to clockwise. We believe our results have potential applications in laser energy focusing, optical tweezers, optical spanners and manufacturing tunable chiral meta-materials.

Mirror and Circular Symmetry of Autofocusing Beams

“…In particular, autofocusing beams acquire additional properties upon a vortex phase inserting [3,[53][54][55]. A more complex modification provides segmentation and complication of the beam structure [4,15,56,57], as well as rotation of a structured beam at propagation [58][59][60]. Another useful property of autofocusing beams is the possibility of forming optical bottles with complex shapes on their basis [61][62][63].…”

Generation of Complex Transverse Energy Flow Distributions with Autofocusing Optical Vortex Beams

“…However, in applications such as microparticles trapping and laser structuring, the transverse field distribution in the focal region is also important. As a rule, variations in the transverse distribution are achieved by amplitude and phase modulation of an axisymmetric beam [ 13 , 14 , 15 , 18 , 19 , 20 , 23 , 33 , 34 , 35 , 36 ].…”

“…The trapped particles move in the direction of the intensity and phase gradient [ 32 ]. One of the methods to vary this distribution is to supplement an axisymmetric autofocusing beam with amplitude and phase modulation [ 13 , 14 , 15 , 18 , 19 , 20 , 23 , 33 , 34 , 35 , 36 ], among which the most interesting is the vortex phase since it is preserved during propagation. Inserting a vortex phase singularity into a laser beam can lead to various polarization and spin-orbit transformations [ 37 , 38 , 39 , 40 ].…”

“…The superposition of optical vortices allows the formation of rotating (spiral) autofocusing beams during propagation, as well as varying the TEFD in the focal area. Autofocusing beams rotating during propagation have attracted the attention of researchers [ 23 , 35 , 36 ] due to the transverse beam structure varying depending on the distance, which expands the possibilities of using such beams in various applications. Note that in these works, to obtain the rotation effect, either the spatial combination of different beams was used, for example, by sectors [ 35 ], rings [ 36 ], or inserting a nonlinear vortex phase into a beam [ 23 ].…”

“…Autofocusing beams rotating during propagation have attracted the attention of researchers [ 23 , 35 , 36 ] due to the transverse beam structure varying depending on the distance, which expands the possibilities of using such beams in various applications. Note that in these works, to obtain the rotation effect, either the spatial combination of different beams was used, for example, by sectors [ 35 ], rings [ 36 ], or inserting a nonlinear vortex phase into a beam [ 23 ]. The second approach is more convenient for experimental implementation; however, the nonlinear vortex phase provides the formation of one type of transverse distribution in the form of a spiral [ 43 ].…”