Wang Guocui, Guo Jinying, Wang Xinke, Hu Bin, Situ Guohai, Zhang Yan
Beijing Engineering Research Center for Mixed Reality and Advanced Display, School of Optics and Photonics, Beijing Institute of Technology, Beijing, 100081, China.
Beijing Key Laboratory of Metamaterials and Devices, Key Laboratory of Terahertz Optoelectronics Ministry of Education, Department of Physics, Capital Normal University, Beijing, 100048, China.
Nanoscale. 2022 Oct 6;14(38):14240-14247. doi: 10.1039/d2nr03827g.
Super cells or multi-layer metasurfaces are used to realize various multi-functional and exotic functional devices. In such methods, the design space expands exponentially as more variable parameters are introduced; however, this will necessitate huge computational effort without special treatment. The function of a metasurface can be described mathematically by using a Jones matrix. When the gap between adjacent atoms is sufficiently large, the overall Jones matrix of a 3D lattice which is composed of multiple meta-atoms can be obtained by adding or multiplying each meta-atom's Jones matrix for a parallel or cascaded arrangement, respectively. Reversely, an arbitrary Jones matrix can be decomposed to achieve a combination of diagonal and rotation matrices. This means that the devices with various functions can be constructed by combining, cascading, and rotating a kind of atom, and thus the computation requirements will be reduced significantly. In this work, the feasibility of this approach is demonstrated with two cases, circular polarization selective transmission and resemble optical activity. Both the simulation and experiment are consistent with the hypothesis. This method can manipulate all degrees of freedom in a Jones matrix and reduce design complexity and may find applications to extend the scope of meta-optics.
超细胞或多层超表面被用于实现各种多功能和奇特的功能器件。在这些方法中，随着更多可变参数的引入，设计空间呈指数级扩展；然而，若没有特殊处理，这将需要巨大的计算量。超表面的功能可以通过琼斯矩阵进行数学描述。当相邻原子之间的间距足够大时，由多个超原子组成的三维晶格的整体琼斯矩阵可以分别通过对每个超原子的琼斯矩阵进行相加（用于平行排列）或相乘（用于级联排列）来获得。反之，任意琼斯矩阵都可以分解以实现对角矩阵和旋转矩阵的组合。这意味着通过组合、级联和旋转一种原子就可以构建具有各种功能的器件，从而显著降低计算需求。在这项工作中，通过圆偏振选择性传输和类似旋光性这两个案例证明了该方法的可行性。模拟和实验均与假设一致。该方法可以操控琼斯矩阵中的所有自由度，降低设计复杂度，并且可能在扩展超光学的应用范围方面找到应用。
