Zhang Q, Gao D L, Gao L
Opt Express. 2021 Mar 29;29(7):9816-9825. doi: 10.1364/OE.420630.
Graphene has taken impressive roles in light manipulation and optical engineering. The most attractive advantage of graphene is its tunable conductivity that could be dynamically modulated by various means. In this paper, we show that the spin Hall shift of light is dynamically tunable via changing the Fermi level of the graphene-wrapped spheres. Such tunability is prominent when different modes interfere with each other, such as at the interference of electric and magnetic dipolar modes or at the interference of electric dipolar and electric quadrupole modes. The circular polarization degree in the near field clearly demonstrates the strength of spin-orbit interaction, which is associated with spin Hall shift of light in the far-field. In addition, the spin Hall effect is shown in far-field detection plane and should be observed in experiment. Our results provide insights into how the spin Hall effect could be tuned and add new perspective in designing optical super-resolution imaging techniques.
石墨烯在光操控和光学工程领域发挥了令人瞩目的作用。石墨烯最具吸引力的优势在于其可调电导率，可通过多种方式进行动态调制。在本文中，我们表明，通过改变包裹石墨烯的球体的费米能级，光的自旋霍尔位移是可以动态调节的。当不同模式相互干涉时，例如电偶极和磁偶极模式的干涉，或者电偶极和电四极模式的干涉时，这种可调性尤为显著。近场中的圆偏振度清楚地表明了自旋 - 轨道相互作用的强度，这与远场中光的自旋霍尔位移相关。此外，自旋霍尔效应在远场检测平面中得到体现，应该能够在实验中被观测到。我们的研究结果为如何调节自旋霍尔效应提供了见解，并为设计光学超分辨率成像技术增添了新的视角。
