Study On The Generation And Propagation Characteristics Of Airy Vortex Beam Array

Airy beams have the characteristics of no diffraction,self-acceleration,and self-healing,which has broad application prospects in many fields,such as cleaning particles,light capturing,plasma energy rotation,and three-dimensional light bullet.Vortex beams have attracted widespread attention in the fields of light manipulation,image enhancement,and high-capacity communications due to their own spiral wave-front phase characteristics.The Airy vortex beam combines the dual characteristics of Airy beam and vortex singularity,which has become a hot research topic at home and abroad in the field of linear or nonlinear laser medicine and laser ablation.The research mainly focuses on the basic research of single right-angle or circular Airy vortex beams.There are few less researches on the issue of spatially multiplexing beams to generate generalized Airy vortex beam arrays,and the experimental optical path to generate related arrays is more complex and phase diaphragm.What's more,the method of generating hologram is complicated,and the light energy utilization rate is low.Aiming at the above problems,a method of generating generalized Airy vortex beam arrays based on Fourier conjugate symmetric extension computer-generated holography is proposed,and its propagation dynamic characteristics are studied.First of all,the Fourier conjugate symmetric continuation calculation holography method is used to generate the Airy vortex beam array phase hologram,which can be multiplexed in the spatial domain.The method of generating the multi-vortex beams is flexible,the method of generating the phase hologram and the experimental light path are relatively simple,and the light energy utilization efficiency is relatively high.Secondly,based on the Poynting vector and Fresnel diffraction integral formula,the propagation dynamic characteristics of Airy vortex beam array are analyzed.Because the propagation velocity of the main lobe of the Airy beam is faster than the propagation speed of the singularity of the vortex,and the main lobe slowly returns to the strongest point during the propagation process,maintaining the self-healing characteristics of the Airy beam.The Airy Vortex Beam Array arranged in a head-to-head manner will have a peak at the center point intensity during the propagation process,realizing the self-focusing process.Deformed Airy vortex beam arrays such as obtuse and acute angles can also return to a right-angle form after a certain distance of propagation,further proving the self-healing characteristic of Airy beam.Finally,the propagation evolution and self-focusing characteristics of an array composed of circular Airy vortex beams with different topological charges or different initial launch angles are analyzed.The results show that larger topological charges can enhance the self-focusing process,including shortening the focusing distance and increasing the focusing intensity of the focal plane.The circular Airy vortex beam with a positive initial emission angle can also enhance the self-focusing process,so the combination of the two parameters can effectively control the propagation dynamics of the circular Airy vortex beam.