论文期刊

Ultra-Broadband Wide-Angle Perfect Absorber in Visible through Thin Grating-Insulator-Metal Structures




作者: Xu Chen, Jiu Hui Wu, Pei Cao
发表/完成日期: 2018-11-21
期刊名称: Journal of the Optical Society of America B
期卷: Vol. 36, No. 2, 2019
相关文章: josab-Ultra_Broadband Wide_Angle Perfect Absorber in Visible through Thin Grating_Insulator_Metal Structures.pdf   
论文简介
A new thin grating-insulator-metal (GIM) structure with ultra-broadband wide-angle perfect absorption is proposed, and a general approach to this kind of multilayered structure is investigated based on the rigorous coupledwave analysis method and the transfer matrix method. On the basis of this approach, the electromagnetic field
distributions in each layer and optical diffraction coefficients are derived theoretically. Compared with a metal–
insulator–metal (MIM) structure, the GIM structure consisting of a metal grating on top of a low-loss dielectric
layer and a bottom metal layer can achieve a higher absorption with the smaller thickness that attributes to the
extraordinary optical transmission of the top grating layer and the cavity resonance of the middle insulator layer.
By optimizing the structural and material parameters, the materials from top to bottom are selected as
Mn-Al2O3-Mn, whose thicknesses are 10 nm, 65 nm, and 70 nm, respectively. With these optimum parameters,
better performance with average absorption over 95% in the visible regime is obtained. Furthermore, this structure retains near-perfect broadband absorption for large incidence angles and different polarizations. The conclusions presented here could have potential applications in optical devices, such as optical displacement
detection and visible light absorption.