Shang Guanyu, Guan Chunsheng, Zhang Kuang, Wu Qun, Liu Jian, Ding Xuemei, Li Haoyu, Burokur Shah Nawaz, Ding Xumin
Opt Lett. 2022 Sep 1;47(17):4504-4507. doi: 10.1364/OL.464854.
Metasurfaces presenting diversified functionalities have broadened the prospect of manipulating the phase, amplitude, and polarization from the optical to microwave fields. Although the frequency-multiplexing strategy is one of the intuitive and effective approaches to expand the number of channels, demonstrations reporting on the combination between directional asymmetric transmission and frequency-multiplexing via an ultrathin flat device are limited. In this study, a novel, to the best of our knowledge, strategy is proposed to generate four independent holographic images under opposite illumination directions at two operating frequencies, utilizing a single metasurface composed of two types of metallic resonators and one grating layer. Specifically, each scattering channel with independent information makes full use of the whole metasurface. Simulation and experimental results show good agreement, highlighting the attractive capabilities of the multi-functional metasurface platform, which provides more freedom for the manipulation of electromagnetic waves.
具有多样化功能的超表面拓宽了从光学到微波领域中操控相位、幅度和极化的前景。尽管频率复用策略是扩展通道数量的直观且有效方法之一，但通过超薄平面器件实现定向非对称传输与频率复用相结合的相关报道却很有限。在本研究中，据我们所知，提出了一种新颖的策略，利用由两种类型的金属谐振器和一个光栅层组成的单个超表面，在两个工作频率下于相反照明方向生成四个独立的全息图像。具体而言，每个携带独立信息的散射通道充分利用了整个超表面。仿真和实验结果显示出良好的一致性，突出了多功能超表面平台的诱人能力，该平台为电磁波操控提供了更多自由度。
