Abstract:

In order to reduce effectively the turbulence effects of optical wave propagation in the atmosphere and explore methods to mitigate turbulence effects, based on the vortex optical wave and Markov approximation theory for optical wave propagation in atmospheric turbulence and utilizing the method of decomposing the vortex beam into the superposition of the spiral harmonics in cylindrical coordinates, the models of the receiving power and crosstalk power are derived, for a non-diffracting vortex Lommel beam transmitted in non-Kolmogorov turbulence by considering inner and outer scales. The influences of the beam and turbulence parameters on the receiving power and crosstalk power are analyzed for Lommel beams propagating in anisotropic turbulence with different intensities and different degrees. The results show that with the increase of the anisotropic degree of turbulence, the receiving power of each angular momentum mode increases and the crosstalk power decreases, and they are greatly influenced by the power exponent for the non-Kolmogorov spectrum. Moreover, when the shape of the Lommel beam is closer to the circular symmetry mode, the effect of turbulence can be mitigated more. Theoretical analysis shows that the propagation property of the Lommel beam in anisotropic atmospheric turbulence is better than that of  the multiple Hankel-Bessel and Laguerre-Gaussian vortex beam.

Key words: vortex beam, non-diffracting Lommel beam, anisotropy, atmospheric turbulence, propagation