湍流大气中环形Airy高斯涡旋光束的强度和相位特性

Intensity and Phase Characteristics of Ring Airy-Gaussian Vortex Beam in Atmospheric Turbulence

采用分步傅里叶算法,研究了湍流大气中环形Airy高斯涡旋光束的传输强度和相位分布特性。对比分析了环形Airy高斯涡旋光束在湍流大气中和在自由空间中传输特性的变化,揭示了传输距离和分布因子对湍流大气中环形Airy高斯涡旋光束平均强度的影响规律。结果表明:由于大气折射率的随机扰动,光束传输过程中相位波前发生畸变。由于轨道角动量的存在,光束的等相位线变成弧线,且随着传输距离的增大,弧线逐渐变得不平滑。湍流大气中环形Airy高斯涡旋光束的平均强度随传输距离的变化呈Airy函数分布,且分布因子越小,光束的相位波前随传输距离的变化越明显,分布因子对光束传输的稳定性和传输质量的影响越大。

In this study,the intensity and phase distributions of a ring Airy-Gaussian vortex beam propagating in atmospheric turbulence are numerically studied based on the split-step Fourier method. The propagation characteristics of the ring Airy-Gaussian vortex beam in atmospheric turbulence are discussed and compared to those in a free space.The impacts of propagation distance and distribution factor on the average intensity of ring AiryGaussian vortex beam in atmospheric turbulence are revealed.Results demonstrate that the phase wavefronts of the beam during the propagation process are distorted due to the random disturbance of the atmospheric refractive index.The equiphase line of the beam turns into an arc due to the orbital angular momentum,and the arc becomes non-smooth gradually with the increase of the propagation distance.In addition,the variation of the average intensity of ring Airy-Gaussian vortex beam with the propagation distance in atmospheric turbulence follows the Airy function distribution.The smaller the distribution factor is,the more obvious the variation of the phase wavefronts with the propagation distance is.The stability and propagation quality of the beam are affected by the distribution factor.