Gomes de Souza Igor Leonardo, Rodriguez-Esquerre Vitaly Felix
Department of Electrical Engineering, Federal University of Bahia, Salvador, 40155-250, Brazil.
Sci Rep. 2019 May 7;9(1):7045. doi: 10.1038/s41598-019-43539-2.
We propose a design approach for color absorbers based on a tri-layer metal-dielectric-metal (MDM) planar geometry, which maintains the same color absorbed, over a range of incident angles from 0° to 80° for light with TM polarization. The dielectrics are chosen to satisfy the ideal conditions of resonance. We calculate the ideal thickness of each dielectric layer by using the planar resonance theory. The numerical results show a total absorption above 85% for all colors of the absorber. We analyzed the influence of the of the metallic top layer thickness and we demonstrated the fabrication error tolerance of the proposed absorber. Finally, we present and discuss the physical mechanisms for the coupling of the electromagnetic field and the absorbed optical power in the structure.
我们提出了一种基于三层金属-电介质-金属（MDM）平面几何结构的吸色器设计方法，对于具有TM偏振的光，在0°至80°的入射角范围内，该结构能保持吸收相同的颜色。选择电介质以满足共振的理想条件。我们利用平面共振理论计算每个电介质层的理想厚度。数值结果表明，该吸色器对所有颜色的光的总吸收率均高于85%。我们分析了金属顶层厚度的影响，并展示了所提出的吸色器的制造误差容限。最后，我们介绍并讨论了该结构中电磁场与吸收光功率耦合的物理机制。
