Purpose

The proposed metamaterial absorber (MMA) has the following advantages: first, the structure of the MMA consists of one planar metallic resonator, which presents a new design approach to obtain a multiband absorption response, rather than using multiple unit-cells in the one large unit cell or stacking different layers. Second, the simultaneous realization of triple-band and dual-band absorption (or bi-functional absorption) at five different frequencies can integrate the respective advantages of the triple functions of the triple-band MMA and double-band MMA, and therefore, the bi-functional MMA will find more application prospects than multiple-functional devices of triple-band and dual-band. Third, the authors simulated the three combinations of MMA here, which is indium tin oxide (ITO)-Polyimide-ITO, ITO-Teflon-ITO and ITO-polyethylene terephthalate (PET)-ITO for the same planar structure and achieve a high absorption rate. Finally, the proposed structure is polarization and angle independent in nature.

Design/methodology/approach

This absorption device consists of the top circular resonator, the middle insulating SiO₂ medium layer and the bottom metallic copper ground plane placed on a substrate. The conductivity of the copper metal is s = 5.8 × 10⁷ s/m. As the transmission of the MMA structure is zero, the substrate materials can be selected randomly. Totally four combinations of terahertz MMA are designed and simulated here which are ITO- SiO₂ –ITO, ITO-Polyimide-ITO, ITO-Teflon-ITO and ITO- PET-ITO for the same planar structure.

Findings

Compared with previous MMAs, the proposed MMA has the following advantages: First, the structure of the MMA consists of one planar metallic resonator, which presents a new design approach to obtain a multiband absorption response, rather than using multiple unit-cells in the one large unit cell or stacking different layers. Second, the simultaneous realization of triple-band and dual-band absorption (or bi-functional absorption) at five different frequencies can integrate the respective advantages of the triple functions of the triple-band MMA and double-band MMA, and therefore, the bi-functional MMA will find more application prospects than multiple-functional devices of triple-band and dual-band. Third, the authors simulated the three combinations of MMA here, which is ITO-polyimide-ITO, ITO-Teflon-ITO and ITO- PET-ITO for the same planar structure and achieve a high absorption rate. Finally, the proposed structure is polarization and angle independent in nature.

Originality/value

First, the structure of the MMA consists of one planar metallic resonator, which presents a new design approach to obtain a multiband absorption response, rather than using multiple unit-cells in the one large unit cell or stacking different layers. Second, the simultaneous realization of triple-band and dual-band absorption (or bi-functional absorption) at five different frequencies can integrate the respective advantages of the triple functions of the triple-band MMA and double-band MMA, and therefore, the bi-functional MMA will find more application prospects than multiple-functional devices of triple-band and dual-band. Third, the authors simulated the three combinations of MMA here, which is ITO-polyimide-ITO, ITO-Teflon-ITO and ITO-PET-ITO for the same planar structure and achieve a high absorption rate. Finally, the proposed structure is polarization and angle independent in nature.

中文翻译：

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光学透明的太赫兹三频和双频超材料吸收器

目的

所提出的超材料吸收器 (MMA) 具有以下优点：首先，MMA 的结构由一个平面金属谐振器组成，这提出了一种获得多波段吸收响应的新设计方法，而不是在一个大的单元中使用多个单元。单元格或堆叠不同的层。其次，在五个不同频率同时实现三频和双频吸收（或双功能吸收），可以综合三频MMA和双频MMA的三重功能各自的优势，因此，双功能MMA将比三频和双频的多功能设备有更多的应用前景。第三，作者在这里模拟了MMA的三种组合，即氧化铟锡（ITO）-聚酰亚胺-ITO，ITO-Teflon-ITO和ITO-聚对苯二甲酸乙二醇酯(PET)-ITO为相同的平面结构并实现了高吸收率。最后，所提出的结构本质上是偏振和角度无关的。

设计/方法/方法

该吸收装置由顶部圆形谐振器、中间绝缘SiO ₂介质层和放置在基板上的底部金属铜接地平面组成。铜金属的电导率为s = 5.8 × 10 ⁷ s/m。由于MMA结构的透射率为零，因此可以随机选择基板材料。这里设计并模拟了四种太赫兹 MMA 组合，即 ITO- SiO ₂ -ITO、ITO-Polyimide-ITO、ITO-Teflon-ITO 和 ITO-PET-ITO，用于相同的平面结构。

发现

与以前的 MMA 相比，所提出的 MMA 具有以下优点：首先，MMA 的结构由一个平面金属谐振器组成，这提出了一种获得多波段吸收响应的新设计方法，而不是在一个单元中使用多个单元。大单元格或堆叠不同的层。其次，在五个不同频率同时实现三频和双频吸收（或双功能吸收），可以综合三频MMA和双频MMA的三重功能各自的优势，因此，双功能MMA将比三频和双频的多功能设备有更多的应用前景。第三，作者在这里模拟了MMA的三种组合，即ITO-polyimide-ITO，ITO-Teflon-ITO 和 ITO-PET-ITO 用于相同的平面结构并实现高吸收率。最后，所提出的结构本质上是偏振和角度无关的。

原创性/价值

首先，MMA 的结构由一个平面金属谐振器组成，它提供了一种新的设计方法来获得多波段吸收响应，而不是在一个大单元中使用多个单元或堆叠不同的层。其次，在五个不同频率同时实现三频和双频吸收（或双功能吸收），可以综合三频MMA和双频MMA的三重功能各自的优势，因此，双功能MMA将比三频和双频的多功能设备有更多的应用前景。第三，作者在这里模拟了三种MMA组合，即ITO-polyimide-ITO、ITO-Teflon-ITO和ITO-PET-ITO，用于相同的平面结构，并实现了高吸收率。最后，