Sorathiya Vishal, Sbeah Zen A, Alghamdi Ahmad, Jaffar Amar Y, Alharbi Abdullah G
Faculty of Engineering and Technology, Parul Institute of Engineering and Technology, Parul University, Waghodia Road, Vadodara, 391760, Gujarat, India.
Department of Mechanical and Industrial Engineering, College of Engineering and Computing in Al-Qunfudhah, Umm al-Qura University, Mecca, Saudi Arabia.
Sci Rep. 2025 Aug 5;15(1):28514. doi: 10.1038/s41598-025-14623-7.
This study utilises simulations to investigate the potential of a novel multi-layered topological insulator-based wideband absorber design. The proposed design is constructed with a multilayer structure that incorporates meticulously chosen materials to enhance light absorption. The top layer is composed of a metal (Fe/Ti/Cu/Zn/Ag/Au), which is followed by an insulating layer (Si/SiO₂/InP) and a topological insulator (Bi₁.₅Sb₀.₅Te₁.₈Se₁.₂). These layers are sandwiched between two metal layers (Fe/Ti/Cu/Zn/Ag/Au). The proposed structure is analysed for two different resonator-based designs, considering both the L-shaped metal resonator and the complementary L-shaped resonator for the overall computational analysis. The overall structure is computed for the broad range of the wavelength spectrum (0.2-1.6 μm). The proposed metamaterial design achieves an absorption rate of ~ 99% across multiple wavelength bands. This structure also investigated the different parametric values, such as physical dimensions and oblique angle of incident, to identify the optimised values of the different parameters. The metamaterial parameters, such as permittivity, permeability, refractive index, and impedance values, are also investigated over the entire wavelength spectrum, which suggests that the overall structure behaves as a double negative material. The wideband metamaterial structure with topological insulator material can also be compared with the interference mode theory.
本研究利用模拟来探究一种基于新型多层拓扑绝缘体的宽带吸收器设计的潜力。所提出的设计采用多层结构，其中包含精心挑选的材料以增强光吸收。顶层由金属（铁/钛/铜/锌/银/金）组成，接着是绝缘层（硅/二氧化硅/磷化铟）和拓扑绝缘体（Bi₁.₅Sb₀.₅Te₁.₈Se₁.₂）。这些层夹在两个金属层（铁/钛/铜/锌/银/金）之间。针对两种不同的基于谐振器的设计对所提出的结构进行分析，在整体计算分析中考虑了L形金属谐振器和互补L形谐振器。针对宽波长范围（0.2 - 1.6微米）对整体结构进行计算。所提出的超材料设计在多个波长带实现了约99%的吸收率。该结构还研究了不同的参数值，如物理尺寸和入射角，以确定不同参数的优化值。还在整个波长范围内研究了超材料参数，如介电常数、磁导率、折射率和阻抗值，这表明整体结构表现为双负材料。具有拓扑绝缘体材料的宽带超材料结构也可以与干涉模式理论进行比较。
