Wang Pan, Han Wenlong, Tao Hui, Zhang Canran, Xu Yijing, Wang Qilong
School of Electronic Science and Engineering, Southeast University, Nanjing 210096, China.
ACS Appl Mater Interfaces. 2024 Jan 17;16(2):2649-2658. doi: 10.1021/acsami.3c16127. Epub 2024 Jan 4.
Reconfigurable multifunctional electromagnetic absorbers have shown broad application prospects in effectively dealing with a series of problems caused by complex electromagnetic environments due to their dynamic reflection wave control characteristics. In this work, we experimentally propose a multifunctional absorber based on a graphene metasurface. Its absorption mode can be flexibly switched among three modes of dual band, broadband, and single band. The reflection amplitude in each absorption mode can be controlled simultaneously. The measurement results of the prepared graphene metasurface indicate that the absorption modes and amplitudes can be dynamically controlled by changing two independent sets of bias voltages applied to the patterned graphene sandwich structures. The proposed graphene metasurface achieves peak absorption rates above 99.9% in both dual-band and single-band absorption modes. Specifically, in the broadband absorption mode, the bandwidth with an absorption rate greater than 90% reaches 17.8 GHz. In addition, it also integrates many advantages, such as optical transparency, polarization-insensitivity, stability of oblique incidence angles, and conformability to the application targets. Therefore, the proposed graphene metasurface is expected to be applied in platforms with optical windows that require resistance to electromagnetic interference and avoidance of electromagnetic radiation.
可重构多功能电磁吸收器因其动态反射波控制特性，在有效应对复杂电磁环境引起的一系列问题方面展现出广阔的应用前景。在这项工作中，我们通过实验提出了一种基于石墨烯超表面的多功能吸收器。其吸收模式可在双频、宽带和单频三种模式之间灵活切换。每种吸收模式下的反射幅度可同时得到控制。对制备的石墨烯超表面的测量结果表明，通过改变施加到图案化石墨烯夹层结构上的两组独立偏置电压，吸收模式和幅度可实现动态控制。所提出的石墨烯超表面在双频和单频吸收模式下均实现了高于99.9%的峰值吸收率。具体而言，在宽带吸收模式下，吸收率大于90%的带宽达到17.8 GHz。此外，它还兼具诸多优点，如光学透明性、偏振不敏感性、斜入射角稳定性以及对应用目标的贴合性。因此，所提出的石墨烯超表面有望应用于需要抗电磁干扰和避免电磁辐射的带有光学窗口的平台。
