Characterizing turbulence-induced orbital angular momentum modes on Gaussian-Schell model beam in the atmosphere with wave-front correction

Superposition theory of spiral harmonics is employed to examine the transmission of turbulence-induced orbital angular momentum (OAM) modes on non-vortex Gaussian-Schell model (GSM) beam in weak to strong atmospheric turbulence. Turbulent aberrations clearly create various OAM modes on GSM beams propagation in the atmosphere, which can be mitigated by applying a wave-front aberration correction method. The effect of wave-front correction method is clearly enhanced by increasing the diameter of circular sampling aperture. As the turbulence strength enhances, low-order OAM modes appear firstly, followed by high-order ones. The probability of turbulence-induced OAM mode decreases, and the peak position of OAM mode probability density deviates from the beam center, as the topological charge increases. Atmospheric turbulence effects degrade the coherence of laser beams when they propagate in the atmosphere. The phase of a laser beam with worse coherence or larger spot size is more sensitive to atmospheric turbulence.