Purpose

The proposed structure consists of copper as a ground plane and 50 µm polyimide dielectric layer is placed in between the ground panel and top radiating patch. Octagon and pentagon shapes are combined to form a unit cell. This structure exhibits seven absorption peaks within the short frequency range 0.3–0.5 terahertz (THz) without any interference. Under normal incidence, this structure achieves the absorption of 96.9%, 95.3%, 98.7%, 91.7%, 96.5%, 95% and 97.8% at 0.3136 THz, 0.377 THz, 0.4060 THz, 0.4085 THz, 0.4240 THz, 0.4436 THz and 0.4648 THz, respectively. This study aims to provide a range of applications in THz dielectric sensing, thickness sensing, communications, wavelength selective radiation and detecting.

Design/methodology/approach

Multi-band THz metamaterial absorbers (MMA) from previous research are having a large unit size because of the presence of stacked layers and multiple resonators within a single unit cell. This leads to difficulty while implementing in practical applications. In this study, a new MMA has been presented at seven distinct frequencies without using stacked layers and multiple resonators.

Findings

This structure exhibits seven absorption peaks within the short frequency range 0.3–0.5 THz without any interference. Under normal incidence this structure achieves the absorption of 96.9%, 95.3%, 98.7%, 91.7%, 96.5%, 95% and 97.8% at 0.3136 THz, 0.377 THz, 0.4060 THz, 0.4085 THz, 0.4240 THz, 0.4436 THz and 0.4648 THz, respectively. The polarization and angle insensitivity of the design have been validated by numerical simulation up to 90° of oblique incidence. The effects of variation in geometrical parameters on absorption response are demonstrated. The physical mechanism of the structure is analysed by electric and magnetic field distributions. The resonant frequency ranges and the number of bands in this work are compared with previously reported papers. In THz range, this is the first time a single planar structure provides seven-band high-level absorption performance.

Originality/value

The highlights of the proposed seven-band THz MMA structure, in comparison with previous THz metamaterials, are as follows: this has a simple unit-cell structure and high resonant mechanism within the short frequency range 0.3–0.5 THz; this MMA can provide seven-band high-level absorption performance in a single planar structure for the first time in THz range; and this structure is polarization and incident angle independent in nature.

中文翻译：

---

0.3-0.5 THz频率的七波段超薄太赫兹超材料吸收器

目的

建议的结构包括铜作为接地平面，50 µm 聚酰亚胺介电层放置在接地面板和顶部辐射贴片之间。八边形和五边形组合在一起形成一个晶胞。这种结构在 0.3-0.5 太赫兹 (THz) 的短频率范围内表现出七个吸收峰，没有任何干扰。在法向入射下，该结构在0.3136 THz、0.377 THz、0.4060 THz、0.4085.34 THz、0.4085.34 THz、0.4085.204 THz、96.9%、95.3%、98.7%、91.7%、96.5%、95%和97.8%的吸收率太赫兹，分别。本研究旨在为太赫兹介电传感、厚度传感、通信、波长选择性辐射和检测提供一系列应用。

设计/方法/方法

由于单个晶胞内存在堆叠层和多个谐振器，来自先前研究的多频段太赫兹超材料吸收器 (MMA) 具有较大的单元尺寸。这导致在实际应用中实施起来很困难。在这项研究中，在不使用堆叠层和多个谐振器的情况下，以七个不同的频率呈现了一种新的 MMA。

发现

这种结构在 0.3-0.5 THz 的短频率范围内表现出七个吸收峰，没有任何干扰。在法向入射下，该结构在 0.3136 THz、0.377 THz、0.4060 THz、0.4085.34 THz、0.4085.34 THz、0.4084 THz 和 0.4084 THz、96.5%、95% 和 97.8% 的吸收率分别达到 96.9%、95.3%、98.7%、91.7%、96.5%、95% 和 97.8% ， 分别。该设计的偏振和角度不敏感性已通过高达 90° 的斜入射角的数值模拟得到验证。证明了几何参数变化对吸收响应的影响。通过电场和磁场分布分析结构的物理机制。将这项工作中的共振频率范围和频段数量与先前报道的论文进行了比较。在太赫兹范围内，

原创性/价值

与以前的太赫兹超材料相比，所提出的七波段太赫兹 MMA 结构的亮点如下：它具有简单的晶胞结构和在 0.3-0.5 THz 短频率范围内的高共振机制；该MMA在太赫兹范围内首次可以在单个平面结构中提供七波段高水平吸收性能；这种结构本质上是偏振和入射角无关的。