Poincaré beams are known to host all three types of Stokes vortices (SVs). We present the optical currents (total transverse energy flow or Poynting vector) in Poincaré beams that contain a bright SV at the center of the beam. Mainly two types of optical flow patterns are observed: circulation at the center and multiple circulation loops around the center. The circulating optical currents are seen only around $S_{12}$ SVs. Open and closed loop-saddle points of the Poynting vector occur in beams containing $S_{23}$ SVs at the center. The number of closed loops in the total transverse flow indicates the magnitude of the ${\sigma }_{23}$ Stokes index. Experimentally obtained energy flow structures in four different Poincaré beams support the theoretical predictions.

中文翻译：

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庞加莱光束中的光电流

庞加莱光束可以容纳所有三种斯托克斯旋涡（SV）。我们介绍了庞加莱光束中的光电流（总横向能量流或Poynting矢量），该光束在光束中心包含明亮的SV。主要观察到两种类型的光流模式：中心的循环和中心附近的多个循环回路。仅在周围看到循环光电流${\mathrm{小号}}_{12}$SV。Poynting向量的开环和闭环鞍点出现在包含${\mathrm{小号}}_{23}$SV位于中心。总横向流中闭环的数量表示${\sigma }_{23}$斯托克斯指数。实验获得的四种庞加莱梁中的能流结构支持理论预测。