Tightly focusing evolution of the auto-focusing linear polarized circular Pearcey Gaussian vortex beams

We report tightly focused characteristics of the auto-focusing linear polarized circular Pearcey Gaussian vortex beams (CPeGVBs) with on-axis and off-axis vortex pairs through high numerical aperture in this paper. Compared with the linear polarized Airy beam, we find that the autofocusing linear polarized CPeGVBs are rotating during the tightly focusing progress. We analyse the relationship between the autofocusing and the tightly focusing of CPeGVBs. At the same time, some cases of the flat-top beam and the quasi optical comb mode generated by the linear polarized CPeGVBs are analyzed in detail, and the changing of the focus depth with beam parameters is also discussed. To show the superiority of linear polarization CPeGVBs, we explore the tightly focusing intensity contrasts of the beams, and we characterize the resulting optical polarization singularity using zero-, one- and two-order topological structures. We present the spin density vector and the polarization ellipse distributions of the CPeGVBs in the x−y plane. Furthermore, the CPeGVBs present two kinds of the spin density vector on the optical axis that one is helix shaped and the other one is oscillating in the one axial direction of CPeGVBs by choosing the appropriate factors. Our results have the potential applications in reverse shaping of focal fields and optical trapping control.