Bilal Rana Muhammad Hasan, Saeed Muhammad Ahsan, Naveed Muhammad Ashar, Zubair Muhammad, Mehmood Muhammad Qasim, Massoud Yehia
Innovative Technologies Laboratories (ITL), King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia.
School of Electrical Engineering, Korea University, Seoul 02841, Korea.
Nanomaterials (Basel). 2022 Sep 27;12(19):3356. doi: 10.3390/nano12193356.
The efficient control of optical light at the nanoscale level attracts marvelous applications, including thermal imaging, energy harvesting, thermal photovoltaics, etc. These applications demand a high-bandwidth, thermally robust, angularly stable, and miniaturized absorber, which is a key challenge to be addressed. So, in this study, the simple and cost-effective solution to attain a high-bandwidth nanostructured absorber is demonstrated. The designed nanoscale absorber is composed of a simple and plain circular ring of nickel metal, which possesses many interesting features, including a miniaturized geometry, easily fabricable design, large operational bandwidth, and polarization insensitivity, over the previously presented absorbers. The proposed nanoscale absorber manifests an average absorption of 93% over a broad optical window from 400 to 2800 nm. Moreover, the detailed analysis of the absorption characteristics is also performed by exciting the optical light's various incident and polarization angles. From the examined outcome, it is concluded that the nanostructured absorber maintains its average absorption of 80% at oblique incident angles in a broad wavelength range from 400 to 2800 nm. Owing to its appealing functionalities, such as the large bandwidth, simple geometry, low cost, polarization insensitivity, and thermal robustness of the constituting metal, nickel (Ni), this nano-absorber is made as an alternative for the applications of energy harvesting, thermal photovoltaics, and emission.
在纳米尺度上对光进行有效控制具有诸多奇妙的应用，包括热成像、能量收集、热光伏等。这些应用需要一种高带宽、热稳定性好、角度稳定且小型化的吸收体，这是一个有待解决的关键挑战。因此，在本研究中，展示了一种实现高带宽纳米结构吸收体的简单且经济高效的解决方案。所设计的纳米级吸收体由一个简单的镍金属圆环组成，与之前提出的吸收体相比，它具有许多有趣的特性，包括小型化的几何结构、易于制造的设计、较大的工作带宽和偏振不敏感性。所提出的纳米级吸收体在400至2800纳米的宽光学窗口内表现出93%的平均吸收率。此外，还通过激发光的各种入射角和偏振角对吸收特性进行了详细分析。从研究结果可以得出结论，该纳米结构吸收体在400至2800纳米的宽波长范围内，在斜入射角下仍能保持80%的平均吸收率。由于其具有吸引人的功能，如大带宽、简单的几何结构、低成本、偏振不敏感性以及构成金属镍（Ni）的热稳定性，这种纳米吸收体可作为能量收集、热光伏和发射应用的替代品。
