The tight-focusing properties of radially polarized symmetrical power-exponent-phase vortex beam

Abstract

In this paper, the radially polarized new kind of power-exponent-phase vortex (NPEPV) beam, with rotationally symmetrical phase structure, was introduced and the tightly focused properties of the radially polarized NPEPV beam passing through a high numerical aperture objective lens were studied numerically. The results show that with the increase of topological charge l, there are multiple intensity points in the focal region, and the number is consistent with the topological charge. In addition, as the power order n increases, the light intensity gradually concentrates on the central optical axis and the surrounding intensity points gradually disappear, which finally presents a Gaussian intensity distribution with the dark cores gradually move away from the optical axis and disappear. These unique properties will have potential applications in particle trapping and laser fabrication, especially for simultaneous trapping of multiple particles and fabrication of chiral microstructures.

Propagation properties of partially coherent radially polarized rotationally-symmetric power-exponent-phase vortex beams in turbulent atmosphere

“…At present, the models of RSPEPVBs mainly include Gaussian [13], LG [12,16], Airy [5,11] and so on. In this paper, the LG RSPEPVBs with single ring structure was mainly discussed and its normalized electric field in the source plane can be expressed as [12]:…”

“…It can be observed in figures 5(a)-(p) that the beam structure changes from hollow to solid as the initial coherence width decreases and propagating distance increases. Initially, the shape of the solid structure is related to the topological charge [16], and subsequently resembles the flat-top beams, but eventually it becomes circular intensity distribution after a sufficient propagation distance as illustrated in figure 6. In general, the profile of the partially coherent RP-RSPEPVB will transform into a Gaussian-like beam more quickly with the decrease of the coherence width.…”

“…So far, the propagation properties of Airy RSPEPVBs [11], fully coherent and partially coherent Gaussian RSPEPVBs in free space [6,9], and the zero-order Laguerre-Gaussian (LG) RSPEPVBs [12] and radially polarized (RP) RSPEPVBs in oceanic turbulence [13], as well as the focusing properties of RP-LG-RSPEPVBs [14] and partially coherent RP-RSPEPVBs [15,16] have been extensively researched. Moreover, the RSPEPVBs have been utilized for optical trapping of multiple particles [10].…”

Statistical Properties of Partially Coherent Higher-Order Laguerre-Gaussian Power-Exponent Phase Vortex Beams

“…Power-exponent phase vortex (PEPV) beams are special optical vortexes with different phase velocities within the transverse dimension [1][2][3][4][5][6]. According to the intensity distribution, PEPV beams can be categorized as asymmetric and rotationally symmetric.…”

“…Specifically, by tuning the spatial coherence of radially polarization beams, it is possible to trap types of particles with different sizes and refractive indices [21,22]. In previous works, we have investigated the propagation properties of partially coherent [3] Laguerre-Gaussian (LG) APEPV beams [1], tightly focused properties of RSPEPV beams [2], and 0-order LG-RSPEPV [25] beams, and pointed out some of their application advantages in optical trapping [10]. However, they may not provide the opportunity to manipulate different types of quantitative particles simultaneously.…”