Generation of perfect vector vortex beams and their propagation in atmospheric turbulence.

Abstract

Perfect vector vortex beams (PVVBs) carry orbital angular momentum (OAM) and exhibit self-focusing and self-healing properties, showing great application potential in free-space optical communication. Based on the pixelated complex amplitude encoding algorithm, we experimentally generate parameter-tunable PVVBs. The multi-phase screen method was adopted for numerical simulations to investigate the propagation characteristics of parameter-varied PVVBs in atmospheric turbulence. Through a comparative analysis of beam wander, beam expansion, and intensity scintillation under corresponding conditions, it is found that the evolution of beam intensity has a notable impact on propagation effects. During the self-focusing stage, beam wander and beam expansion increase significantly as turbulence intensity strengthens, whereas the scintillation index tends to plateau, resulting in scintillation saturation. Increasing the topological charge enlarges the effective beam radius; additionally, a larger topological charge mitigates turbulence-induced disturbances, leading to a slower radius expansion rate as turbulence intensity increases. Increasing the ring radius or decreasing the ring width can reduce light intensity scintillation and increase the effective beam radius. The scintillation index decreases gradually as the polarization state approaches that of cylindrical vector beams, indicating that rational modulation of the beam polarization state is an effective and feasible approach to suppress intensity scintillation. This research offers valuable insights for the application of PVVBs in atmospheric microwave remote sensing, aerospace, and military defense scenarios.