Sugic Danica, Dennis Mark R
J Opt Soc Am A Opt Image Sci Vis. 2018 Dec 1;35(12):1987-1999. doi: 10.1364/JOSAA.35.001987.
As the size of an optical vortex knot, imprinted in a coherent light beam, is decreased, nonparaxial effects alter the structure of the knotted optical singularity. For knot structures approaching the scale of wavelength, longitudinal polarization effects become non-negligible, and the electric and magnetic fields differ, leading to intertwined knotted nodal structures in the transverse and longitudinal polarization components, which we call a knot bundle of polarization singularities. We analyze their structure using polynomial beam approximations and numerical diffraction theory. The analysis reveals features of spin-orbit effects and polarization topology in tightly focused geometry, and we propose an experiment to measure this phenomenon.
当印刻在相干光束中的光学涡旋结的尺寸减小时，非傍轴效应会改变打结光学奇点的结构。对于接近波长尺度的结结构，纵向偏振效应变得不可忽略，并且电场和磁场不同，导致横向和纵向偏振分量中出现相互缠绕的打结节点结构，我们将其称为偏振奇点的结束。我们使用多项式光束近似和数值衍射理论分析它们的结构。该分析揭示了紧聚焦几何结构中自旋 - 轨道效应和偏振拓扑的特征，并且我们提出了一个实验来测量这种现象。
