The Mie resonances of high-index nanostructures offer the possibility of manipulating light with extremely low loss. Enhanced optical magnetism, with a concomitant significant increase in the quality factor, can be achieved in high-index metasurfaces by adding a highly reflective backplane to the system. Here, we show that Mie-resonance-based hybrid metasurfaces consisting of an array of amorphous silicon nanodisks on a gold backplane can be used to manipulate light polarization upon reflection. Reflection matrix analysis reveals the nontrivial topological property associated with the Mie resonance of individual nanodisks. The topologically protected polarization conversion effect allows the generation of abundant and diverse polarization in the reflected waves by varying the incident wavevector. By presenting proof-of-concept demonstrations based on nonlinear modeling, we further show that the considered hybrid metasurfaces can serve as a platform for ultrafast all-optical polarization switching of near-infrared light. The topological nature of the metasurfaces’ response offers great flexibility in polarization generation and dynamic modulation.

中文翻译：

---

利用基于三重共振的混合超表面的拓扑特性进行光的超快切换

高折射率纳米结构的Mie共振提供了以极低的损耗操纵光的可能性。通过向系统添加高反射背板，可以在高折射率超颖表面上实现增强的光磁，同时提高品质因数。在这里，我们表明，由金底板上的非晶硅纳米盘阵列组成的基于米氏共振的混合超表面可用于操纵反射时的光偏振。反射矩阵分析揭示了与单个纳米盘的Mie共振相关的非平凡的拓扑特性。受拓扑保护的偏振转换效应允许通过改变入射波矢量在反射波中生成丰富多样的偏振。通过基于非线性建模的概念验证演示，我们进一步表明，所考虑的混合超表面可以充当近红外光超快全光偏振切换的平台。超表面响应的拓扑性质为极化生成和动态调制提供了极大的灵活性。