近日，印度理工学院德里分校的Manisha&Hemant Kumar Singh及其研究团队取得一项新进展。经过不懈努力，他们揭示空间相关可控矢量涡旋光束的斯托克斯闪烁现象。相关研究成果已于2024年4月16日在国际知名学术期刊《物理评论A》上发表。

本文报道了对空间相关可控聚焦矢量涡旋光束(VVBs)的斯托克斯闪烁(SS)的理论和实验观测。研究人员首先利用高斯-谢尔模型（GSM）源成功生成了部分相干VVBs（PC-VVBs）。聚焦后的PC-VVBs在光束截面上展现出优化的SS参数极值表现。聚焦PC-VVB的SS参数呈现出独特的空间结构化行为。研究进一步揭示，空间相关性、极化分布的非均匀性以及Poincaré-Hopf指数（PHI）是塑造SS参数结构的关键因素。值得一提的是，研究人员观察到SS参数之间存在一种互补关系。

此外，研究人员还深入探讨了与斯托克斯闪烁（SS）参数相关的简并度，进一步完善了研究内容。特定的SS参数呈现出的花型分布特征，提供了确定部分相干矢量涡旋光束（PC-VVBs）拓扑指数的有效手段。有趣的是，在PC-VVBs中，SS参数的束缚条件和互补性质在跨光束截面的闪烁压缩方面展现出了实际应用价值。具体表现为，其中一个SS参数可以通过牺牲另一个SS参数的方式被有效抑制。因此，在实际应用中，可以根据源的相关性和拓扑特征，通过微调约束条件来充分利用这一效应。

附：英文原文

Title: Stokes scintillations for vector vortex beams with controllable spatial correlation

Author: Manisha, Hemant Kumar Singh, P. Senthilkumaran, Bhaskar Kanseri

Issue&Volume: 2024/04/16

Abstract: The present work reports the theoretical and experimental observation of Stokes scintillations (SS) for focused vector vortex beams (VVBs) with controllable spatial correlation. Initially, a Gaussian-Schell model (GSM) source is utilized to generate the partially coherent VVBs (PC-VVBs). The focusing of PC-VVBs results in the optimization of extremum values of SS parameters across the beam cross section. Additionally, the SS parameters of the focused PC-VVB show spatially structured behavior. It is found that the spatial correlation, the inhomogeneous polarization distribution, and the Poincaré-Hopf index (PHI) of VVBs are important factors for structuring the SS parameters. The SS parameters are observed to exhibit a complementary relationship. Furthermore, the degeneracy associated with the SS parameters is discussed to complete the study. The flower-patterned distribution of specific SS parameters is useful in determining the topological index of the PC-VVBs. Interestingly, the bound condition and complementary nature of SS parameters are useful for scintillation squeezing across the beam cross section in PC-VVBs, where one SS parameter is suppressed at the expense of another. Thus, the source can be finely tuned using the bound condition with correlation and topological features to harness this effect optimally.

DOI: 10.1103/PhysRevA.109.043516

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.109.043516