近日，西北工业大学的赵建林&李鹏及其研究团队取得一项新进展。经过不懈努力，他们揭示离轴极化奇点诱导的可控光子自旋霍尔效应。相关研究成果已于2024年7月17日在国际知名学术期刊《物理评论A》上发表。

本文通过在自由空间中设计离轴极化奇点来实现PSHE，揭示了离轴矢量光束可控自旋-轨道耦合与轨道角动量谱之间的关系。数值模拟和实验结果表明，极化奇点的嵌入位置和极化顺序以及垂直于极化奇点离轴方向的分离方向对自旋相关的分离距离和OAM光谱有影响。这项研究工作为利用自旋光子进行基于光学自旋电子学的信息处理提供了一条可行而简单的途径。

据悉，高效的光子自旋霍尔效应(PSHE)对自旋光子器件的应用具有重要意义，但由于介质界面处的折射或反射引起的自旋相关分离很小，无法在实际中应用。

附：英文原文

Title: Controllable photonic spin Hall effect induced by an off-axis polarization singularity

Author: Xiang Zhang, Yanke Li, Yuan Zhang, Bingyan Wei, Sheng Liu, Yi Zhang, Peng Li, Jianlin Zhao

Issue&Volume: 2024/07/17

Abstract: The photonic spin Hall effect (PSHE) with high efficiency is of significance for the application of spin photonic devices, but the spin-dependent separation induced by the refraction or reflection at the interface of the media is too tiny to be used in practice. In this paper, we realize a PSHE by designing off-axis polarization singularity in free space and reveal the relationship between controllable spin-orbit coupling and orbital angular momentum (OAM) spectra of the off-axis vector beam. The numerical simulations and experimental results show that the spin-dependent separated distance and the OAM spectra are manipulated by the embedded position and polarization order of polarization singularity, and the separating direction perpendicular to the off-axis direction of polarization singularity. Our work provides a feasible and simple path for manipulating spin photons toward information processing based on optical spintronics.

DOI: 10.1103/PhysRevA.110.013511

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.013511