Opt Express. 2023 Feb 27;31(5):8453-8464. doi: 10.1364/OE.482653.
Large-scale, and high-throughput produced devices with strong ultrabroadband absorption and high angular tolerance are in demand for applications such as thermal imaging, energy harvesting, and radiative cooling. Despite long-standing efforts in design and fabrication, it has been challenging to achieve all these desired properties simultaneously. Here, we create a metamaterial-based infrared absorber fabricated from thin films of epsilon-near-zero (ENZ) materials grown on metal-coated patterned silicon substrates that exhibit ultrabroadband infrared absorption in both p- and s-polarization at angles ranging from 0° to 40°. The results show that the structured multilayered ENZ films exhibit high absorption (> 0.9) covering the entire 8∼14 µm wavelengths. In addition, the structured surface can be realized via scalable, low-cost methods on large-area substrates. Overcoming the limitations on angular and polarized response improves performance for applications such as thermal camouflage, radiative cooling for solar cell, thermal image and et., al.
对于热成像、能量收集和辐射冷却等应用，人们需要具有强超宽吸收和高角度容忍度的大规模、高通量生产的器件。尽管在设计和制造方面进行了长期的努力，但同时实现所有这些理想特性一直具有挑战性。在这里，我们创建了一种基于超材料的红外吸收器，该吸收器由在金属涂层图案化硅衬底上生长的近零介电常数（ENZ）材料的薄膜制成，在 0°到 40°的角度范围内，在 p 和 s 偏振下均表现出超宽的红外吸收。结果表明，结构化多层 ENZ 薄膜在整个 8∼14μm 波长范围内表现出高吸收率（>0.9）。此外，结构化表面可以通过可扩展的、低成本的方法在大面积衬底上实现。克服角度和偏振响应的限制，提高了热伪装、太阳能电池辐射冷却、热成像等应用的性能。
