Mou Nanli, Tang Bing, Li Jingzhou, Dong Hongxing, Zhang Long
Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China.
Key Laboratory of Materials for High-Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.
Sci Rep. 2022 Feb 15;12(1):2501. doi: 10.1038/s41598-022-04772-4.
Metamaterial absorbers (MMAs) offer a novel and flexible method to realize perfect absorption in specific frequencies, especially in the THz range. Despite the exotic abilities to manipulate light, most previously reported MMAs still suffer from limited bandwidth and tunability. Here we present a thermally switchable terahertz (THz) metasurface that exhibits ultra-broadband absorption and high-transmission characteristics at different ambient temperatures. Our simulations demonstrate that at room temperature the structure is highly transparent. When the ambient temperature reaches 358 K, the proposed design exhibits an ultra-broadband absorption from 0.398 to 1.356 THz with the absorptivity maintaining above 90% and the relative absorption bandwidth reaches up to 109.2%. The structure is demonstrated to be insensitive to the incident angle. Moreover, the bandwidth of such a structure can easily be expanded or reduced by cascading or removing the rings, providing high scalability in practical applications. Such a thermally switchable THz metasurface may have potential applications in various fields, such as optical switching, THz imaging, modulating and filtering.
超材料吸收体（MMAs）提供了一种新颖且灵活的方法来实现特定频率下的完美吸收，尤其是在太赫兹频段。尽管具有操控光的奇特能力，但此前报道的大多数超材料吸收体仍存在带宽和可调性有限的问题。在此，我们展示了一种可热切换的太赫兹（THz）超表面，其在不同环境温度下呈现出超宽带吸收和高透射特性。我们的模拟表明，在室温下该结构具有高度透明性。当环境温度达到358 K时，所提出的设计在0.398至1.356 THz范围内呈现超宽带吸收，吸收率保持在90%以上，相对吸收带宽高达109.2%。该结构被证明对入射角不敏感。此外，通过级联或移除环，这种结构的带宽可以轻松扩展或缩小，在实际应用中具有高度可扩展性。这种可热切换的太赫兹超表面可能在光学开关、太赫兹成像、调制和滤波等各个领域具有潜在应用。
