Propagation properties and radiation forces of the Hermite-Gaussian vortex beam in a medium with a parabolic refractive index

Focusing pattern of the Laguerre-Gaussian beam with polarization mixing helical-conical phase modulation

This paper focuses on the focusing pattern of the Laguerre-Gaussian (LG) beam with polarization mixing helical-conical phase modulation, which is based on the vector diffraction theory. The results show that the topological charge number l can sensitively control the intensity of the intensity peaks. The focal spot will split along the optical axis under different polarization parameters P. When l=1, the spot position and the peak intensity can be modulated by changing the polarization parameter P. The truncation parameter β makes the focusing spot form an optical trap. By adjusting the eccentricity parameter K, the opening direction of the optical trap can be well controlled. These results may be helpful in optical applications such as optical manipulation, optical focusing, and optical information transmission.

Propagation dynamics of the odd-Pearcey Gaussian beam in a parabolic potential

In this paper, the propagation properties of the odd-Pearcey Gaussian beam (OPGB) in a parabolic potential are investigated analytically and numerically. Except for the auto-focusing at the focal plane, the OPGB performs a weak off-axis focusing unexpectedly. The focusing distance and the focal intensity can be adjusted by choosing an appropriate parabolic parameter. Also, the Poynting vector of the OPGB is demonstrated. In addition, we investigate the radiation forces of the OPGB and find that the trapping points can be generated during propagation.

Simultaneous Trapping of Two Types of Particles with Focused Elegant Third-Order Hermite-Gaussian Beams

The focusing properties of elegant third-order Hermite-Gaussian beams (TH₃GBs) and the radiation forces exerted on dielectric spherical particles produced by such beams in the Rayleigh scattering regime have been theoretically studied. Numerical results indicate that the elegant TH₃GBs can be used to simultaneously trap and manipulate nanosized dielectric spheres with refractive indexes lower than the surrounding medium at the focus and those with refractive indexes larger than the surrounding medium in the focal vicinity. Furthermore, by changing the radius of the beam waist, the transverse trapping range and stiffness at the focal plane can be changed.