Vector Laguerre-Gauss beams with polarization-OAM entanglement in a graded-index medium

TL;DR

This paper demonstrates that vector-vortex Laguerre-Gauss modes with polarization-OAM entanglement are solutions to Maxwell's equations in a graded-index medium, analyzing focusing, wave evolution, and revival effects in optical waveguides.

Contribution

It introduces vector solutions of Maxwell's equations for polarization-OAM entangled modes in graded-index media and studies their focusing and revival behaviors.

Findings

Wave shape varies with distance due to spin-orbit and nonparaxial effects.

Periodic revival of wave packets occurs due to mode interference.

High-efficiency transfer of focused spots over large distances is achieved.

Abstract

It is shown that the vector-vortex Laguerre-Gauss modes with polarization-orbital angular momentum (OAM) entanglement are the vector solutions of the Maxwell equations in a graded-index medium. Focusing of linearly and circularly polarized vortex light beams with nonzero azimuthal and radial indices in a cylindrical graded-index medium is investigated. The wave shape variation with distance taking into account the spin-orbit and nonparaxial effects is analyzed. Effect of long-term periodical revival of wave packets due to mode interference in a graded-index cylindrical optical waveguide is demonstrated. High efficiency transfer of a strongly focused spot through an optical waveguide over large distances takes place with a period of revival.