Lu Cheng-Yu, Chung Chin-Chien, Yen Ta-Jen, Huang Tsung-Yu
Department of Materials Engineering, Ming Chi University of Technology, New Taipei, 24301, Taiwan, ROC.
Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan, ROC.
Sci Rep. 2021 Sep 21;11(1):18713. doi: 10.1038/s41598-021-98077-7.
In this work, we integrated a periodic seed layer and oblique deposition method to fabricate a stochastically-distributed oblique-flat-sheet metamaterial perfect absorber (MPA). Such design could increase its absorption bandwidth and tolerance to high angle-incidence due to the fact that various oblique flat sheets offer different resonance conditions while even a single oblique flat sheet could provide different optical paths for resonance. On the other hand, a seed layer could reduce uncertainty regarding to direct oblique deposition and provide abilities to manipulate the bandwidth of the MPA. We also setup a simulation model in the aids of Visual Basic Application and examined the absorption behavior of the MPA under TM and TE oblique incidence that could achieve high absorbance under 80° and 60° incidence, respectively. Finally, in measurement, the fabricated sample owns 65% absorbance within 80-250 THz and over 90% absorbance within 250-320 THz at x-polarization normal incidence; as for the y-polarization normal incidence, we could achieve overall 70% absorbance within 80-300 THz. The measured results reveal similar tendency compared to the simulated ones.
在这项工作中，我们集成了周期性种子层和倾斜沉积方法来制造随机分布的倾斜平板超材料完美吸收体（MPA）。这种设计可以增加其吸收带宽和对大角度入射的耐受性，因为各种倾斜平板提供了不同的共振条件，而且即使是单个倾斜平板也可以为共振提供不同的光路。另一方面，种子层可以减少直接倾斜沉积的不确定性，并提供操纵MPA带宽的能力。我们还借助Visual Basic应用程序建立了一个模拟模型，并研究了MPA在TM和TE倾斜入射下的吸收行为，在80°和60°入射角下分别可实现高吸收率。最后，在测量中，制备的样品在x偏振垂直入射时，在80 - 250太赫兹范围内具有65%的吸收率，在250 - 320太赫兹范围内吸收率超过90%；对于y偏振垂直入射，在80 - 300太赫兹范围内总体吸收率可达70%。测量结果与模拟结果显示出相似的趋势。
