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This paper introduces the propagation properties and polarization characteristics of radially polarized partially coherent vortex beams in anisotropic plasma turbulence and discusses in detail the distribution of light intensity in such beams as a function of propagation distance. In addition, we analyze how the parameters of the anisotropic plasma turbulence affect the degree of polarization, polarization orientation angle, and degree of ellipticity of the beam. The results show that the degree of polarization of the radially polarized partially coherent vortex beam satisfies the modification of the central origin zero and the gradual increase with the radius during plasma turbulent propagation. At the same time, smaller turbulence eddies in the anisotropic plasma turbulence render, more obvious the irregular structure perpendicular to the vortex-stretching direction, the smaller the influence on the polarization characteristics of the radially polarized partially coherent vortex beam. It is advantageous to the research on optical communication and the study of anisotropic plasma turbulence. [ABSTRACT FROM AUTHOR]

Highlights • Propagation model of radially polarized vortex beams in atmospheric turbulence is established. • A radially polarized vortex beam can reduce beam spreading and wander effects in the atmosphere. • Polarization modulation can be an approach to mitigate turbulent effects on OAM-based systems. Abstract Adopting a vortex beam with poor coherence can reduce turbulence-induced beam spreading and wander effects in the atmosphere, but it intensifies the degradation rate of its beam profile from a doughnut shape into a Gaussian shape. Transmission quality of Orbital–angular–momentum (OAM) mode carried by a vortex beam is closely related to its evolution of intensity distribution. After appropriate polarization modulation, a radially polarized vortex beam has a better performance on the reduction of beam spreading and wander effects than its scalar counterpart. A radially polarized vortex beam can also lower the degradation rate of its beam profile and keep "OAM information" a longer distance. Therefore, appropriate polarization modulation can be an effective approach to mitigate the adverse turbulent effects on OAM-based systems operated in the atmosphere. [ABSTRACT FROM AUTHOR]

Analytical expressions of average intensity and long-term beam width for a radially polarized multi-Gaussian Schell-model (MGSM) beam in anisotropic atmospheric turbulence are developed based on the extended Huygens-Fresnel principle. The influences of anisotropic non-Kolmogorov turbulence and source parameters on the average intensity, polarization and long-term beam spreading of radially polarized MGSM beam are examined in detail. The source correlations, free-space diffraction and turbulent effect jointly affect both the intensity and polarization profiles of the beam propagated in the atmosphere. As a radially polarized MGSM beam propagates in the atmosphere, increasing the associated beam order can lower the evolution rate from its flat-topped beam profile into a Gaussian beam profile because of the turbulent effect. Variations in the average intensity and long-term beam width are closely related to the propagation distance, power spectrum index, inner-scale, initial spatial coherence, and beam width. The atmospheric turbulence-induced beam spreading is generally suppressed with the enhanced anisotropy coefficient. [ABSTRACT FROM AUTHOR]