The narrowband meta-absorbers exhibit significantly enhanced electromagnetic confinement capabilities, showcasing broad application prospects in sensing fields. They can be applied for biomarker detection, chemical composition analysis, and monitoring of specific gas in the environment. In this work, we propose a 3D meta-absorber with an out-of-plane plasma mechanism based on a two-photon printing system. Compared to the conventional fabrication of a metal-insulator-metal 2D meta-absorber, the 3D absorber is composed of a metal layer and a resin layer from top to bottom; its manufacturing process is simpler, only including two-photon printing and magnetron sputtering deposition. A noticeable absorbing resonance appears at 0.3142 THz with perfect absorbance with a high Q$Q$-factor of 104.67. The theoretical sensitivity to the refractive index of the sensor reaches up to 172.5 GHz/RIU, with a figure of merit (FOM) of 19.56. In the experiments, it was validated as a meta-absorber with high sensitivity for doxycycline (DCH). As the DCH concentration increases from 0 to 4 mg/mL, the absorption intensity decreases around 49%, while the resonant frequency shift is around 70 GHz. It reflects the real-time residual content of DCH, and is potentially applied in trace antibiotic detection. The results showcase a perfect narrowband absorption capability with strong electromagnetic confinement in the terahertz spectrum, along with high-Q$Q$ sensing characteristics of DCH. Compared to 2D metamaterials, the diversity of 3D metamaterial significantly expands, and introduces additional effects to provide greater flexibility in manipulating electromagnetic waves. The 3D device offers opportunities for the application of terahertz biochemical sensing.

中文翻译：

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基于双光子聚合打印的 3D 元吸收芯片太赫兹传感

窄带超吸收体表现出显着增强的电磁约束能力，在传感领域展现出广阔的应用前景。它们可应用于生物标志物检测、化学成分分析以及环境中特定气体的监测。在这项工作中，我们提出了一种基于双光子打印系统的具有平面外等离子体机制的 3D 元吸收器。与传统制造的金属-绝缘体-金属2D超吸收体相比，3D吸收体从上到下由金属层和树脂层组成；其制造工艺较为简单，仅包括双光子印刷和磁控溅射沉积。在 0.3142 THz 处出现明显的吸收共振，具有完美的吸光度和104.67 的高Q$Q$因子。该传感器对折射率的理论灵敏度高达172.5 GHz/RIU，品质因数（FOM）为19.56。在实验中，它被验证为对强力霉素（DCH）具有高敏感性的元吸收剂。随着 DCH 浓度从 0 增加到 4 mg/mL，吸收强度下降约 49%，而谐振频移约为 70 GHz。它反映了DCH的实时残留含量，在痕量抗生素检测中具有潜在的应用前景。结果展示了太赫兹频谱中完美的窄带吸收能力和强电磁限制，以及DCH 的高Q$Q$传感特性。与2D超材料相比，3D超材料的多样性显着扩展，并引入了额外的效应，为操纵电磁波提供了更大的灵活性。 3D设备为太赫兹生化传感的应用提供了机会。