Effect of oceanic turbulence with anisotropy on the propagation of multi-sinc Schell-model beams

Abstract

Using the extended Huygens-Fresnel principle, the expressions for the cross-spectral density function of both the circular and square multi-sinc Schell-model (MSSM) beams propagating in an anisotropic oceanic turbulent medium have been derived respectively. Based on the expression, the effects of the oceanic turbulence parameters and the anisotropic factor on the intensity and coherence properties of such beams are explored explicitly. By comparative analysis with the case in free space, it is shown that the adjustable multi-ring and square lattice intensity structures of the MSSM beam in ocean are shaped to be circular flat-topped, square flat-topped or Gaussian-like due to different strength of turbulence. The unique intensity patterns can be maintained for a relatively long propagation distance as the anisotropic factor increases. Furthermore, it is found that the turbulent parameters including the salinity and temperature contribution factor, rate of dissipation of turbulent kinetic energy and rate of dissipation of the mean squared temperature have less impacts on the propagation behaviors of the MSSM beam in anisotropic oceanic turbulence in comparison to the corresponding isotropic case. The results presented here have potential applications in oceanic optical telecommunication links.

Keywords

• Anisotropic turbulence
• multi-sinc Schell-model correlation
• Beam propagation
• Spectral intensity