Design and study of phosphorene nanoribbons as a perfect absorber and polarizer in mid-IR range

Abstract

Two-dimensional materials because of their unique physical and chemical properties made changes in the last two decades. Phosphorene, as a member of the 2D materials family, is a semiconductor material with a bandgap 0.2eV that leads to many applications in field-effect transistors, cathode/anode materials in batteries, energy storage, optical gas sensors, and so on. Due to the optical properties of phosphorene in the IR and THz regime, this paper aims to improve the rate of phosphorene absorption. This absorption uptake by surface plasmon resonance in one-dimensional nanostructures. For this purpose, the optical properties of phosphorene nanoribbons in the IR regime investigate. By using a dielectric substrate and a metal reflecting layer, the localization of SPR on phosphorene increases from 20% to an almost perfect system. In this process, the anisotropic properties of phosphorene increased. This makes the proposed structure a good option for polarizers in the IR region. In addition, the optical properties and materials, as well as geometry, have been studied and optimized. The resulting system is a board-angel absorber that shows little dependence on the reflective layer and dielectric medium. Simulations have been performed using the FEM method in COMSOL Multiphysics software. • In this paper, with aim of creating perfect absorber, a structure based on phosphorene proposed. Then, optical properties of monolayer phosphorene nanoribbons in IR range investigated and optimized. • Firstly, the absorption of phosphorene with dielectric substrate was reported to be 20%, then, by applying a metal reflective layer under the structure, Surface Plasmon's become more localized, so the structure become almost perfect absorber system. • In this process, the optical properties, material, and geometry have been studied and optimized. The resulting optical absorber shows minimal dependence on the reflective metal layer, dielectric substrate, and incident light angle. • This system can be utilize as a strong polarizer in IR-Range due to its difference of 2% between the zigzag and armchair directions to about 100%.