Near and far field propagation properties of hollow Gaussian beam in non-Kolmogorov turbulence

Abstract

Based on the Hypergeometric function properties, the analytical expression for the average intensity of Hollow Gaussian beam (HGB) propagating through non-Kolmogorov turbulence is derived. In the near field, influences of generalized refractive-index structure parameter C˜n2, generalized exponent α, beam waist w0 and order of beam n on the dark size of HGB are studied. It is found that changes of dark size with C˜n2, w0, n are monotonic, i.e., dark size decreases as C˜n2 increases, as w0 and n decrease. Besides, the dependence of dark size on α is not monotonic and the dark size is the smallest when α=3.11. In addition, effect of the aforementioned parameters on the spreading of laser beam is investigated in the far filed. It is shown that the beam spreads more seriously for a higher generalized refractive-index structure parameter, a smaller beam waist, a lower beam order, and generalized exponent located at α=3.11.