Yuan, YangshengCai, YangjianQu, JunEyyuboglu, Halil T.Bayka, YahyaKorotkova, Olga2016-05-122025-09-182016-05-122025-09-182009Yuan, Y...et al. (2009). M-2-factor of coherent and partially coherent dark hollow beams propagating in turbulent atmosphere. Optics Express, 17(20), 17344-17356. http://dx.doi.org/10.1364/OE.17.0173441094-4087https://doi.org/10.1364/OE.17.017344https://hdl.handle.net/20.500.12416/14920Analytical formula is derived for the M-2-factor of coherent and partially coherent dark hollow beams (DHB) in turbulent atmosphere based on the extended Huygens-Fresnel integral and the second-order moments of the Wigner distribution function. Our numerical results show that the M-2-factor of a DHB in turbulent atmosphere increases on propagation, which is much different from its invariant properties in free-space, and is mainly determined by the parameters of the beam and the atmosphere. The relative M-2-factor of a DHB increases slower than that of Gaussian and flat-topped beams on propagation, which means a DHB is less affected by the atmospheric turbulence than Gaussian and flat-topped beams. Furthermore, the relative M-2-factor of a DHB with lower coherence, longer wavelength and larger dark size is less affected by the atmospheric turbulence. Our results will be useful in long-distance free-space optical communications. (C) 2009 Optical Society of Americaeninfo:eu-repo/semantics/openAccessArticle10.1364/OE.17.0173442-s2.0-70349706235