光子自旋霍尔效应及其在物性参数测量中的应用

光子自旋霍尔效应是指光束在非均匀介质中传输时，自旋角动量相反的光子在垂直于入射 面的方向发生的横向自旋相关分裂。光子自旋霍尔效应可以和电子自旋霍尔效应作类比：自旋光 子扮演自旋电子的角色，折射率梯度扮演外场的角色。光子自旋霍尔效应源于光的自旋-轨道相互 作用，和两类几何相位有关：一类是动量空间的自旋重定向Rytov-Vlasimirskii-Berry 相位；另 一类是斯托克斯参数空间的Pancharatnam-Berry 相位。光子自旋霍尔效应对物性参数非常敏感， 结合量子弱测量技术，在物性参数测量、光学传感等领域具有重要的应用前景。本文将简单分析 光子自旋霍尔效应的物理根源，回顾近几年不同物理系统中光子自旋霍尔效应的研究进展，介绍 光子自旋霍尔效应在物性参数测量中的应用。最后，展望其在光学模拟运算、显微成像、量子成 像等领域的可能发展方向。

Spin Hall Effect of Light and Its Applications in Measurements of Physical Parameters

The spin Hall effect (SHE) of light refers to the transverse spin-dependent splitting of photons with opposite spin angular momentum after the beam passes through inhomogeneous media, in the direction perpendicular to the incident plane. It can be regarded as an analogue of the SHE in electronic systems, where the spin photons and the refractive index gradient replace the spin electrons and the electronic potential, respectively. Fundamentally, the SHE of light originates from the spin-orbit interaction of photons and depends mainly on two different geometric phases, namely, the spin redirection Rytov-Vlasimirskii-Berry phase in the momentum space and the Pancharatnam-Berry phase in the Stokes parameter space. Meanwhile, the SHE of light exhibits great sensitivity to the physical parameters, and combined with quantum weak measurements, has important application prospects in fields of physical parameters measurement and optical sensing. We briefly analyze the physical origin of the SHE of light, review its recent progress in different physical systems, and present its applications in measurements of physical parameters. Finally, the possible developing trends in optical analog computing, microscopy imaging, and quantum imaging are discussed.