A dual-band terahertz metamaterial absorber composed of two identical square metallic patches and an insulating medium layer on top of a continuous metallic ground is demonstrated. Two resonance peaks (labeled A and B) with near 100% absorbance are obtained, of which peak A derived from the localized resonance of the two square patches has a line-width of 0.2571 THz and quality factor of 6.9156, while peak B which resulted from the hybrid coupling of the localized resonance of the two square patches and surface lattice resonance of the device has a very narrow line-width of 0.0083 THz and large quality factor of 296.2771. Narrow line-width and large quality factor have important prospects in sensing application. Based on this, the sensing performance of the device is explored; it is revealed that peak B exhibits highly sensitive sensing ability (including a sensing sensitivity of 1.9010 THz per RIU and figure of merit of 229.04) in terms of the surrounding index. In addition, the influence of structural parameters on the absorption performance is discussed to further verify the formation mechanism of these two absorption peaks.

中文翻译：

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使用两个相同的方形贴片设计用于传感应用的双波段太赫兹超材料吸收器

演示了由两个相同的方形金属贴片和连续金属接地顶部的绝缘介质层组成的双波段太赫兹超材料吸收器。获得了两个吸光度接近 100% 的共振峰（标记为 A 和 B），其中来自两个方形贴片的局部共振的峰 A 的线宽为 0.2571 THz，品质因数为 6.9156，而峰 B 导致从两个方形贴片的局部共振和器件的表面晶格共振的混合耦合来看，该器件的线宽非常窄，为 0.0083 THz，品质因数为 296.2771。窄线宽和大品质因数在传感应用中具有重要的应用前景。在此基础上，探索了器件的传感性能；结果表明，就周围指数而言，峰 B 表现出高度敏感的传感能力（包括每 RIU 1.9010 THz 的传感灵敏度和 229.04 的品质因数）。此外，还讨论了结构参数对吸收性能的影响，以进一步验证这两个吸收峰的形成机理。