中国激光, 2019, 46 (7): 0705001, 网络出版: 2019-07-11
涡旋光束在海洋湍流中传输的闪烁因子 下载: 1215次
Scintillation Index of Vortex Beams Propagating in Oceanic Turbulence
光束传输与控制 闪烁因子 涡旋光束 海洋湍流 传输 beam propagation and control scintillation index vortex beam oceanic turbulence propagation
摘要
采用分步相位屏方法仿真涡旋光束在海洋中的传输,并对涡旋光束在海洋湍流中传输的光强和闪烁因子进行仿真计算。研究发现,随着传输距离的增加,涡旋光束的光斑逐渐扩散开来,且中心暗斑也在逐渐消失。通过改变湍流相位屏参数模拟不同强度的海洋湍流,发现随着均方温度耗散率变大,或温度、盐度波动的相对强度变大,或单位质量液体中的湍流动能耗散率变小,涡旋光束的轴上点闪烁因子也会变大。当传输距离达到一定值时,涡旋光束的闪烁因子会逐渐低于高斯光束,且拓扑荷数越大闪烁因子降低得越明显。
Abstract
The intensity and scintillation index of vortex beams propagating in the oceanic turbulence are simulated by using a step-by-step phase screen method. We find that the vortex beam spot diffuses gradually and the central dark spot gradually disappears with increase in the propagation distance. By changing the parameters of the turbulent phase screen to simulate the oceanic turbulence with different strengths, we find that the on-axis scintillation index of the vortex beam increases with increase of the mean-square temperature dissipation rate, increase of the relative strength of temperature and salinity fluctuations, or decrease of turbulent kinetic energy dissipation rate per unit mass of fluid. The scintillation index of the vortex beam is lower than that of the Gaussian beam when the propagation distance reaches a certain value, and the larger the topological charge is, the more rapidly the scintillation index descends.
张凯宁, 刘永欣, 蒲继雄. 涡旋光束在海洋湍流中传输的闪烁因子[J]. 中国激光, 2019, 46(7): 0705001. Kaining Zhang, Yongxin Liu, Jixiong Pu. Scintillation Index of Vortex Beams Propagating in Oceanic Turbulence[J]. Chinese Journal of Lasers, 2019, 46(7): 0705001.