Study On Propagation Properties Of Partially Coherent Of Multi-Gaussian Schell-model Beams In Anisotropic Turbulence

In recent years,the propagation properties of laser beams in turbulence atmosphere have been attracted many researchers'interests due to their widely applications in optical communication,laser ranging and so on.It is necessary to study the influence of turbulence parameters on the propagation of beams in turbulence atmosphere,because of the beam is affected by turbulence when it is propagated in the atmosphere.The theory of turbulence based on Kolmogorov model for beams propagation in turbulence atmosphere has been extensively studied.However,more experimental data currently indicate that the areas of turbulence atmosphere contain anisotropic statistical properties.The Kolmogorov model sometimes cannot accurately describe the statistical laws of actual atmospheric turbulence.Scholars have shown that the intensity distribution of partially coherent beams are more uniform than that of completely coherent beams,and the partially coherent beam with special correlation structure exhibits distinctive properties.Therefore,the reasonable selection of beam types to reduce the effects of atmospheric turbulence has a certain significance for free-space optical communication.In view of this,based on anisotropic power spectrum of refractive index fluctuations,we study the propagation properties of multi-Gaussian Schell-model(MGSM)beams and electromagnetic elliptical multi-Gaussian Schell-model(EEMGSM)beams in anisotropic turbulence.The primary research contents are as follows,(1)Based on the extended Huygens-Fresnel principle,the expressions of degree of coherence,ellipticity,and beam wander of MGSM beam through the anisotropic turbulence are derived.The statistical properties of them in anisotropic turbulence are illustrated numerically.It is found that the MGSM beam is significantly less affected by anisotropic turbulence compared with Gaussian Schell-model(GSM)beam.(2)Based on the Wigner distribution function and the extended Huygens-Fresnel principle,the expressions of propagation factor(known asM~2-factor)of the EEMGSM beam through the anisotropic turbulence are derived.The statistical properties,such as theM~2-factor an EEMGSM beam in anisotropic turbulence are illustrated numerically.It is found that the EEMGSM beam is significantly less affected by anisotropic turbulence compared with elliptic Gaussian Schell-model(EGSM)beam.