Steady-state thermal blooming effect of vortex beam propagation through the atmosphere

Abstract

Based on the fast Fourier transform algorithm, the steady-state thermal blooming effect of a vortex beam propagation in the atmosphere is investigated using the multiple phase-screen simulation method. The variations of propagation distance, initial power, transverse wind speed, atmospheric absorption coefficient, initial radius and wavelength are demonstrated to illustrate the change in the thermal blooming effect. The results show that the thermal blooming effect can be enhanced by increasing the initial power, propagation distance and atmospheric absorption coefficient of a vortex beam propagation in the atmosphere without changing other parameters. In contrast, increasing the transverse wind speed, initial radius, and wavelength can reduce the thermal blooming effect. As a comparison method, based on the first order perturbations, the analytical expression of steady-state thermal blooming of a vortex beam propagation in the atmosphere is obtained. The variation law of the thermal blooming distortion and transversely centroid position with different parameters of vortex beam propagation in the atmosphere are analyzed in detail. Based on the comparison of two different methods, the results show that the simulation results obtained by the multi-phase screen method and the analytical results obtained by the first order perturbation method are basically the same in the near field propagation, but with the increase of the propagation distance, the results obtained by the two methods are significant differences.