Herein, we have presented a computation study of a metasurface (MS) narrowband perfect absorber performed utilizing the three-dimensional finite element method. In the first part of the paper, the periodic sequence of silicon meta-atoms (MAs) is positioned on a ∼100 nm gold thin-film. The gold thin-film obstructs a broadband light at normal incidence, and silicon MAs are utilized to stimulate the surface plasmon by scattering light through it. The highest absorption of 96% is procured at 930.26 nm in the air medium which can be further enhanced by using a layered structure of MAs deposited on gold. The MAs are composed of Si/SiO₂/Si with an optimized layers height. Consequently, the perfect impedance matching of the electric and magnetic dipoles takes place providing a 99% of absorption insensitive to the incidence angle of light and almost negligible reflection at a resonating wavelength of 889.4 nm. This feature allows us to utilize this device as a plasmonic sensor. That is why, in the second part of the paper, the proposed device design is studied for the detection of the refractive index of the surrounding medium. The sensitivity and figure of merits of the MS device are in the range of 460–492 nm RIU⁻¹ and 76.7–82 RIU⁻¹, respectively. We claim that the anticipated MS element can be employed in solar photovoltaic and biomedical sensing purposes.

在此，我们提出了利用三维有限元方法对超表面 (MS) 窄带完美吸收器进行的计算研究。在论文的第一部分，硅元原子 (MAs) 的周期序列位于 100 nm 的金薄膜上。金薄膜阻挡了法向入射的宽带光，硅 MA 用于通过散射光来刺激表面等离子体激元。在空气介质中的 930.26 nm 处获得了 96% 的最高吸收率，这可以通过使用沉积在金上的 MAs 层状结构进一步增强。MA 由 Si/SiO _{2 组成}/Si 具有优化的层高。因此，电偶极子和磁偶极子的完美阻抗匹配发生提供 99% 的吸收，对光的入射角不敏感，并且在 889.4 nm 的谐振波长下几乎可以忽略不计的反射。此功能允许我们将该设备用作等离子体传感器。这就是为什么在本文的第二部分中，研究了所提议的设备设计以检测周围介质的折射率。MS 设备的灵敏度和品质因数分别在 460-492 nm RIU ^-1和 76.7-82 RIU ^-1的范围内。我们声称预期的 MS 元件可用于太阳能光伏和生物医学传感目的。