Broadband infrared polarizer of graphene wire grids with flat PER curves

Since 2004, the flourishing two-dimensional graphene has sparked extensive research on graphene-based optical and optoelectronic devices with high performance due to its ultra-fast photoelectric response, broadband, and tunable optical response. However, up until now, graphene-based wire grid polarizers have not been demonstrated to perform excellent characteristics with flat polarization extinction ratio (PER) curves, while they all exhibited narrow peak-shaped working bands. Here, we propose a broadband polarizer based on graphene wire grids with a flat PER curve of up to similar to 84.5 dB in the ultrawide range of 1-10 mu m. In the range of <4 mu m, the graphene wire grid polarizer exhibits a strong plasmon resonance effect and outputs a linear-polarized state. Its performance is closely related to carrier density that is tuned by the Fermi level (EF) and thickness of graphene. (c) 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).