Propagation of Tricomi-Gaussian beams in a chiral medium

Abstract

In this paper, propagation of a newly introduced Tricomi-Gaussian beam in a chiral medium is investigated for the first time. By using the Collins diffraction integral formula and matrix optical theory, analytical expression of Tricomi-Gaussian beams through an ABCD optical system is obtained, and the propagation characteristics are discussed. Results demonstrate that Tricomi-Gaussian beams would reduce to general, asymmetrical Bessel-Gaussian beams, or Gaussian-like beams by selecting appropriate complex constant β. Evolution of the beam intensity presents a clockwise rotation along the propagating direction, and the central dark area increases when propagating in free space. When propagating through a chiral medium, Tricomi-Gaussian beams would split into a left-circularly polarized (LCP) beam and a right-circularly polarized (RCP) beam with distinct propagation trajectories. Furthermore, it is also demonstrated that the trajectory divergence and intensity variations of two circularly polarized beams could be regulated by the chiral parameter γ. In addition, the intensity distribution of the LCP and RCP beams exhibits greater sensitivity to the chiral parameter in the far field than that in the near field. These obtained results could find potential applications in the fields of optical sorting and optical manipulation.

Keywords

• Tricomi-Gaussian beams
• Chiral medium
• Propagation