Propagation properties of partially coherent Laguerre-Gaussian beams in turbulent atmosphere

To study the propagation properties of partially coherent Laguerre-Gaussian (PLG) beams through turbulent atmosphere, the analytical formulas are derived for the angular width and the beam-propagation factor (M-2-factor) of PLC beams by using the extended Huygens-Fresnel principle and the second-order moments of the Wigner distribution function (WDF). The corresponding numerical results are also calculated. When propagation distance increases, the angular width is found to spread faster for PLC beams with higher beam order, smaller correlation length and bigger structure constant C-n(2) The angular width of PLC beams decreases with increase in waist width (w(o)).The M-2-factor of PLC beams with higher beam order and smaller correlation length is less affected by turbulence with increase in propagation distance. The propagation properties of the M-2-factor for PLC beams with the smaller structure constant C-n(2) are better than that with bigger structure constant C-n(2). The M-2-factor of PLC beams decreases with increase in the wavelength lambda, and it is also less affected by turbulence for beams with higher order and smaller correlation length. Furthermore, for the PLC beams with the same beam order, the angular width and the M-2-factor keep invariable in free space. (C) 2010 Elsevier Ltd. All rights reserved.