Multifunctional analysis and verification of lightning-type electromagnetic metasurfaces

• Published in: Optics express Vol. 30; no. 10; pp. 17008 - 17025
• Main Authors: Xu, Jie, Tang, Jian, Cheng, Yu, Chen, Ming, Wang, Hexuan, Xiong, Jianfeng, Wang, Tianrang, Wang, Shuaizhao, Zhang, Youdan, Wen, Hui, Qu, Shiliang, Yuan, Libo
• Format: Journal Article
• Language: English
• Published: 09-05-2022
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.458412

Aiming at the problems that most of the existing electromagnetic metasurfaces have single function and narrow application scope, a highly integrated lightning-type metasurface is proposed in this study. It can realize the functions of circular dichroism (CD), absorption of electromagnetic waves, broadband x-to-y cross polarization conversion (CPC) function, linear-to-circular polarization conversion (LTC-PC) function and asymmetric transmission (AT), and its functions are also analyzed and verified. The designed metasurface consists of the bottom grating structure, the lower SiO 2 , the middle lightning-type graphene, the upper SiO 2 , the top graphene and photosensitive silicon. Through numerical calculations, the CD of design can reach more than 85% at 4.22 THz. The function of bimodal absorption is achieved at 4.09 and 8.69 THz. At 7.41∼8.21 THz, the polarization conversion ratio (PCR) of the metasurface reaches more than 99%. Simultaneously, the function of LTC-PC can be formed when PCR is 50%. Finally, when the designed metasurface is in the transmissive state, the AT of design is close to 60% at 7.84 THz. This design provides a new design idea and method for biomedical detection, image processing, modulators, smart switches, optical diodes and other fields.