Terahertz (THz) absorbers have recently attracted extensive attention for their promising potential in various applications; however, many existing THz absorbers are restrained by their narrow bandwidth and complicated and costly fabrication process that renders them unfavorable for practical devices. Herein, we propose a stereoscopic multilayered ultrabroadband THz metamaterial absorber by stacking multilayer concentric resonators on different-level top surfaces of a monolithic three-dimensional (3D) pagodalike substrate. By taking full advantage of the 3D printing technique, the proposed ultrabroadband absorber can be produced efficiently in an easy three-step process that overcomes the fabrication complexities of traditional multistep photolithography processes. Additionally, the feasibility and robustness of the proposed fabrication method for common out-of-plane THz narrowband absorbers are also validated, and the absorption capacities of the 3D printed absorbers are numerically and experimentally elucidated. These results might provide an efficient concept and fabrication technique to stimulate many potential applications in emerging THz technologies, such as sensing, imaging, and wireless communications.

中文翻译：

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三维印刷超宽带太赫兹超材料吸收体

太赫兹 (THz) 吸收器最近因其在各种应用中的潜力而受到广泛关注。然而，许多现有的太赫兹吸收器受限于其窄带宽和复杂且昂贵的制造工艺，使其不利于实际设备。在此，我们通过在单片三维（3D）宝塔状基板的不同水平顶面上堆叠多层同心谐振器，提出了立体多层超宽带太赫兹超材料吸收器。通过充分利用 3D 打印技术，所提出的超宽带吸收体可以通过简单的三步工艺高效生产，克服了传统多步光刻工艺的制造复杂性。此外，还验证了所提出的用于常见面外 THz 窄带吸收器的制造方法的可行性和稳健性，并通过数值和实验阐明了 3D 打印吸收器的吸收能力。这些结果可能提供一种有效的概念和制造技术，以刺激新兴太赫兹技术中的许多潜在应用，例如传感、成像和无线通信。