Metamaterial-Based Broadband Adsorbent Containing Molybdenum Disulfide Monolayer via Surface Plasmon Structures

In recent years, an effective interaction of light and two-dimensional materials such as transition metal dichalcogenides has received widespread attention in the fields of nanophotonics and optoelectronics. Nonetheless, the extreme thinness of these materials limits their ability to absorb enough light, especially in practical applications. To overcome the challenge of limited absorption, integrating the monolayers with plasmonic structures has emerged as an effective strategy to significantly boost the interaction between light and these monolayers and improve the material’s overall optical properties. In this paper, we propose a novel design for a broadband optical absorber aimed at enhancing the visible and near-infrared light absorption in MoS₂ monolayers as one of the most common transition metal dichalcogenides. The proposed structure consists of a relatively simple unit cell configuration that achieves an absorption rate exceeding 90% over the wavelength range of 650 to 850 nm, as demonstrated by simulation results. The simulations were conducted using Lumerical software, which employs the finite-difference time-domain method for solving Maxwell’s equations in both time and space.