整数与分数阶涡旋光束相位奇点的稳定性分析  

Stabilization analysis of phase singularity of vortex beams with integral and fractional orders

作　　者：丁攀峰[1] 

机构地区：[1]华侨大学信息科学与工程学院,福建泉州362021

出　　处：《华中科技大学学报（自然科学版）》2011年第5期118-122,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：福建省自然科学基金资助项目(A0810012)

摘　　要：通过衍射积分理论对整数阶以及分数阶涡旋光束的相位奇点的稳定性进行了研究.对于任意整数阶涡旋光束,推导了其在传输中电场的解析表达式;对于分数阶涡旋光束,不能给出传输中电场的解析解,仅能解析计算中心点电场在传输中的值.理论证明和模拟计算表明整数阶涡旋光束的相位奇点具有稳定性,传输后涡旋的暗核能够得以维持,光强仍然具有中心对称性分布;分数阶涡旋光束不具备稳定性,传输后几何中心电场不再为零,且观测平面上的光强分布也不再具有中心对称的特点.实验分析表明整数阶涡旋光束更适合于自由空间光通信系统.The stabilization of the center phase singularity for the vortex beam with integral and fractional order was studied by the method of diffraction-integration theory. For the vortex beam with integral orders, the analytical expression of the electric field was deduced while propagating; for the vortex beams with fractional orders, the analytical expression of the electric field could not be obtained after propagation. Only the central electronic field could be analytically provided. Theoretical analysis and numerical simulation show the phase singularity of the integral order vortex beam is stable, the vortex can preserve and the intensity distribution exhibits centrosymmetrie character after propagation; however, the phase singularity of the fractional order vortex beam is unstable, the electric field of the center is not equal to zero and the intensity distribution has no character of centrosym-metry after propagation. Experiment shows that the vortex beam with integral order is more suitable for free-space optical communication system.

关 键 词：涡旋光束 稳定性 光强分布 整数阶 分数阶 

分 类 号：O436.1[机械工程—光学工程]