A wide-angle and TE/TM polarization-insensitive terahertz metamaterial near-perfect absorber based on a multi-layer plasmonic structure. Issue 14 (23rd June 2021)

• Record Type: Journal Article
• Authors: Sun, Yuanbo; Shi, Yanpeng; Liu, Xiaoyu; Song, Jinmei; Li, Meiping; Wang, Xiaodong; Yang, Fuhua
• Is Part Of: Nanoscale advances. Volume 3:Issue 14(2021)
• Page Start: 4072
• Page End: 4078
• Publication Date: 2021-06-23
• Subjects: 620.5
• DOI: 10.1039/d1na00246e
• Languages: English
• ISSNs: 2516-0230

Abstract

Abstract : This paper proposes a flexible method to design absorbers, each of which exhibits specific absorbing function. Especially for multi-band absorber, the number of absorption peaks is successfully increased without reducing the absorptance of each peak or changing their position. Abstract : A kind of near-perfect metamaterial absorber, made of only Au and Si, has been presented in the terahertz band with extremely high absorptance. A flexible design method is proposed, which could create absorbers with four independent functions as follows. First, selective perfect absorption is achieved at a single frequency, which means the absorptance is more than 99.9% at the required frequency and almost 0% at adjacent frequencies. Second, nearly 100% perfect absorption is realized at more frequencies, which can be changed by simply adjusting the geometric parameters. Third, broadband absorption with a controllable band is gained, and the average absorptance exceeds 99% from 1.2 to 2 THz. Finally, the combination of single-frequency absorption and broadband absorption is accomplished, which greatly expands the application prospects of the proposed absorber. Besides, the absorber exhibits high performance over a wide range of incident angles from 0° to 60°. Meanwhile, it is insensitive to both TE and TM waves. The aforementioned design idea can be extended to other bands.