Li Na, Li Yubo, Yu Di, Song Haoyuan, Zhang Qiang, Zhou Sheng, Fu Shufang, Wang Xuanzhang
Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education and School of Physics and Electronic Engineering, Harbin Normal University, Harbin, 150025, China.
Department of Basic Courses, Guangzhou Maritime University, Guangzhou, 510725, China.
Sci Rep. 2024 Nov 25;14(1):29130. doi: 10.1038/s41598-024-80711-9.
We theoretically study the Goos-Hänchen (GH) and Imbert-Fedorov (IF) shifts of a reflected Gaussian beam from a hyperbolic metasurface composed of graphene grating based on topological insulators (TIs). Perturbations are generated on the surface of TIs by applying a thin magnetic film, resulting in a broken time-reversal symmetry. The GH and IF shifts are greatly enhanced as a result of the combined interaction of the graphene grating and the topological magnetoelectric effect (TME). In particular, even with the p-polarized incident beam near Brewster angles, the magnitude of IF shifts is increased by approximately two orders when compared to the case without graphene or a single layer of graphene. A critical frequency is identified when the propagation model in TIs transitions from a surface wave to a bulk wave, which leads to comparatively substantial GH shifts with high reflection. By adjusting the filling ratio, chemical potential and rotation angle of the graphene grating, the shift of GH and IF can be controlled. The dependence of the spatial shifts on the TME and the degree of anisotropy of the TI are also discussed. Our results may provide new possibilities for applications of the TI with the TME.
我们从理论上研究了基于拓扑绝缘体（TI）的石墨烯光栅构成的双曲超表面反射高斯光束的古斯-汉欣（GH）位移和因伯特-费多罗夫（IF）位移。通过施加一层薄磁膜在TI表面产生微扰，导致时间反演对称性破缺。由于石墨烯光栅与拓扑磁电效应（TME）的联合相互作用，GH和IF位移得到极大增强。特别地，即使对于接近布儒斯特角的p偏振入射光束，与没有石墨烯或单层石墨烯的情况相比，IF位移的大小增加了约两个数量级。当TI中的传播模型从表面波转变为体波时，确定了一个临界频率，这导致具有高反射率的相对较大的GH位移。通过调整石墨烯光栅的填充率、化学势和旋转角度，可以控制GH和IF的位移。还讨论了空间位移对TME和TI各向异性程度的依赖性。我们的结果可能为具有TME的TI的应用提供新的可能性。
