Beam Properties of a Partially Coherent Beam Propagating Horizontally in Atmospheric Turbulence

Abstract

This study explored the impact of atmospheric turbulence on partially coherent light propagation. Atmospheric turbulence causes random modulation of the intensity and phase of light, resulting in a speckle pattern in the far field. This study focused on partially coherent Gaussian Schell model beams and derived an analytical expression of the cross-spectral density function for their transmission through atmospheric turbulence, based on the generalized Huygens–Fresnel principle and the Tatarski spectrum model. Numerical simulations were used to investigate the effects of the source parameters and turbulence strength on the intensity distribution, beam width, and coherence length of partially coherent light in horizontal atmospheric transmission. The results demonstrate that diffraction-induced broadening primarily affects the intensity distribution of light in free-space transmission. Short transmission distances in atmospheric turbulence have comparable characteristics to those in a vacuum; however, as the turbulence intensity and transmission distance increase, the beam broadening effect amplifies, and the coherence length is reduced. The findings are relevant to the design of acquisition, pointing, and tracking systems for wireless laser communication systems and offer insights into the optimization of optical systems for atmospheric conditions.

Evolution properties of partially coherent electromagnetic elliptical vortex beam propagating through atmospheric turbulence

“…The expression of the electric field of electromagnetic elliptical vortex beam (EEVB) at the plane of incidence as follows [28,30]:…”

“…Although the research is mainly focused on the circular beam, there is still literature indicating that ellipticity beam can be less affected by atmospheric turbulence [25][26][27][28][29] and guarantees the beams quality [25]. In addition, elliptical beam has received increasing interest in the fields of optical trapping for accelerated motion of microscopic particles along an elliptical trajectory, in quantum informatics for detecting OAM-entangled photons [30], optical communication [25], etc.…”

“…On the other hand, turbulent atmosphere [30][31][32][33][34][35] causes the beam wander and intensity scintillation by inducing the intensity and phase fluctuation of beam, thus significantly impacting practical application. In addition, it is well known that we use power spectral models to describe atmospheric turbulence to date, and various power spectral models have been proposed, such as Kolmogorov spectrum, Tatarskii spectrum, von Karman spectrum, and non-Kolmogorov spectrum.…”

Average Intensity of a Laguerre—Gaussian Vector Vortex Beam through Inhomogeneous Atmospheric Turbulence

“…Equation (3), especially, reduces to the cross-spectral density (CSD) W αβ (r 1 ,r 2 ;0) of a radially polarized vortex beam for n = 0 and m = 0, a radially polarized hollow beam for m = 0 and n = 0 and a radially polarized beam for n = 0 and m = 0, respectively. With the validity of approximate paraxial solutions, the elements of CSDM for a partially coherent LGVV beam propagating through inhomogeneous atmospheric turbulence can be related with those in the source plane with the help of the following extended Huygens-Fresnel principle integral formula [31][32][33][34][35]:…”