Long-distance propagation of pseudo-partially coherent Gaussian Schell-model beams in atmospheric turbulence

Abstract

Propagation properties of spatially pseudo-partially coherent Gaussian Schell-model beams through the atmospheric turbulence over a long-distance uplink path are studied by numerical simulation. A linear coordination transformation is introduced to overcome the window effect and the loss-of-resolution problem. The beam spreading, beam wandering, and intensity scintillation as functions of turbulence strength, source correlation length, and change frequency of random phase that models the partial coherence of the source are analyzed. It is found that the beam spreading and the intensity scintillation of the partially coherent beam are less affected by the turbulence than those of the coherent one, but it suffers from a more severe diffractive effect, and the change frequency of random phase has no evident influence on it. The beam wandering is insensitive to the variation of source correlation length, and decreases firstly then goes to a fixed value as the change frequency increases.

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“…In recent years, much work has been carried out concerning the spreading and directionality of different laser beams in atmospheric turbulence. [1][2][3][4][5][6][7][8][9][10][11] It has been shown that the turbulence results in broadening and partially coherent beams are less sensitive to the turbulence than fully coherent ones. [1][2][3][4][5][6][7] In 2003, Shirai et al [8] pointed out that under a certain condition there exist equivalent Gaussian Schell-model (GSM) beams that may have the same directionality (i.e., the same angular spread) as a fully coherent Gaussian laser beam in Kolmogorov turbulence.…”

“…[1][2][3][4][5][6][7][8][9][10][11] It has been shown that the turbulence results in broadening and partially coherent beams are less sensitive to the turbulence than fully coherent ones. [1][2][3][4][5][6][7] In 2003, Shirai et al [8] pointed out that under a certain condition there exist equivalent Gaussian Schell-model (GSM) beams that may have the same directionality (i.e., the same angular spread) as a fully coherent Gaussian laser beam in Kolmogorov turbulence. In 2008, we [11] extended this result from GSM beams to general beams, i.e., general beams may generate the same angular spread as a fully coherent Gaussian laser beam both in free space and in Kolmogorov turbulence if the diffractive coefficients of the mean-squared beam width are the same.…”