Zhang Ke, Deng Ruixiang, Song Lixin, Zhang Tao
Appl Opt. 2020 Oct 1;59(28):8878-8885. doi: 10.1364/AO.405135.
In this paper, we propose and numerically investigate an ultra-broadband, wide-angle, and polarization-independent metasurface absorber based on periodic hexagon-latticed titanium (Ti) nanoring arrays over a continuous Ti film. The proposed absorber can achieve more than 90% absorptivity under normal incidence, ranging from 350 to 1453 nm, and the average absorption is up to 95.6%. Additionally, the absorptivity still remained beyond 70% when the incident angles varied from 0° to 60°. The simulations of electric field distributions indicate that the broadband absorption performance can be ascribed to the superposition of the localized surface plasmon resonance (LSPR) originated from the nanopillars and nanoholes, respectively. The proposed approach is simple and inexpensive, and the metal material is optional. Therefore, we believe that the proposed absorber will be a candidate for many potential applications, such as thermophotovoltaic cells, thermal emitters, and optoelectronic devices.
在本文中，我们提出并通过数值研究了一种基于连续钛（Ti）薄膜上的周期性六边形晶格钛（Ti）纳米环阵列的超宽带、广角且偏振无关的超表面吸收器。所提出的吸收器在垂直入射时，在350至1453纳米范围内可实现超过90%的吸收率，平均吸收率高达95.6%。此外，当入射角从0°变化到60°时，吸收率仍保持在70%以上。电场分布模拟表明，宽带吸收性能可归因于分别源自纳米柱和纳米孔的局域表面等离子体共振（LSPR）的叠加。所提出的方法简单且成本低廉，金属材料可任选。因此，我们相信所提出的吸收器将成为许多潜在应用的候选者，如热光伏电池、热发射器和光电器件。
