Autofocusing capabilities of double-ring circular Airy Gaussian beams and their application in particle manipulation

Focusing is extensively researched in bio imaging, medicine, and quantum computation. Due to single focal point and short focal length, which restrict imaging and optical manipulation at long distances. In this paper, we propose a simple method, that is, the coherent superposition of double-ring circular Airy Gaussian beams (DR-CAiGBs) to realize multiple autofocusing over long distances. Without complicated structures, theoretical simulations and experimental verifications demonstrate that the DR-CAiGBs can produce multiple autofocusing points in the optical axis, whose positions and numbers can be flexibly adjusted. Furthermore, we demonstrated the three-dimensional (3D) particle capture capability of the DR-CAiGBs by trapping multiple particles at different autofocusing points over ten centimeters away from the focal plane. Our study and findings pave new avenues for practical applications in biological cell analysis, particle transportation, and lithography.