Zhenhai Sun

Study on power coupling of annular vortex beam propagating through a two-Cassegrain-telescope optical system in turbulent atmosphere

As a new attractive application of the vortex beams, power coupling of annular vortex beam propagating through a two- Cassegrain-telescope optical system in turbulent atmosphere has been investigated. A typical model of annular vortex beam propagating through a two-Cassegrain-telescope optical system is established, the general analytical expression of vortex beams with limited apertures and the analytical formulas for the average intensity distribution at the receiver plane are derived. Under the H-V 5/7 turbulence model, the average intensity distribution at the receiver plane and power coupling efficiency of the optical system are numerically calculated, and the influences of the optical topological charge, the laser wavelength, the propagation path and the receiver apertures on the power coupling efficiency are analyzed. These studies reveal that the average intensity distribution at the receiver plane presents a central dark hollow profile, which is suitable for power coupling by the Cassegrain telescope receiver. In the optical system with optimized parameters, power coupling efficiency can keep in high values with the increase of the propagation distance. Under the atmospheric turbulent conditions, great advantages of vortex beam in power coupling of the two-Cassegrain-telescope optical system are shown in comparison with beam without vortex.

Properties of the flattened-vortex beam with aperture propagating through the turbulent atmosphere in a slant path

Abstract. A typical model of the flattened-vortex beam propagating through the turbulent atmosphere in a slant path is established, and the analytical formulas of the average intensity distribution at the observation plane are derived based on the extended Huygens-Fresnel principle. Under the H-V 5/7 turbulence model, the characteristics of the average intensity distribution at the observation plane are investigated, and the influences of the optical topological charge, the propagation distance, and the zenith angle of the propagation path are numerically analyzed.

Study on the annular vortex beams with limited apertures and their propagation characteristics in the turbulent atmosphere

Considerable interest has been exhibited in characteristics of vortex beams due to their importance in basic science and some attractive applications. The general expression of vortex beams with limited aperture is developed, and the analytical formulas for the average intensity distribution of annular vortex beam with limited aperture in the turbulent atmosphere are derived based on the extended Huygens-Fresnel principle. Under the H-V 5/7 turbulence model, the characteristics of the annular vortex beams with limited apertures propagation through the turbulent atmosphere in a slant path are analyzed in the present paper.