Average spreading of a linear Gaussian-Schell model beam array in non-Kolmogorov turbulence

The average spreading of a linear Gaussian-Schell model (GSM) beam array in non-Kolmogorov turbulence is studied, where the coherent combination is considered. The effects of the beam number, the separation distance between two adjacent beams and the generalized exponent on the root-mean-square (rms) beam width are investigated. The results indicate that the rms beam width in non-Kolmogorov turbulence is different from that in Kolmogorov turbulence, and there is an optimum beam number that leads to a minimum beam width. Further, the beam width can reach the minimum value by adopting the optimum separation distance, which decreases with the increase of beam number. Besides, the partially coherent beam array is less sensitive to the atmospheric turbulence than the fully coherent one.