Graphene-Based Metamaterial Absorber with Perfect Multi-band Absorption.

In this paper, we propose an absorber with adjustable single-layer graphene multi-band perfect absorption, which has the advantages of simple structure, polarization insensitivity, tunability, multi-band absorption, and high sensitivity. The device can achieve four perfect absorption peaks at the same time, and the absorption rate of all absorption peaks is above 99%. The absorption effect of the absorber can be efficiently adjusted and controlled by adjusting the geometric parameters of the single-layer graphene array and the thickness of the dielectric layer. In addition, by changing the strength of the applied magnetic field, the Fermi level, and the relaxation rate of graphene, the absorption of the device can be dynamically adjusted, and high absorption can be maintained in the range of 0°–70° wide incidence angle. Finally, considering the potential sensing applications of the device, we measured maximum sensitivity (S) of 3.06 THz/RIU and a maximum figure of merit (FOM) of 54.6 when exposed to different ambient refractive indices, suggesting that the device can be used as a refractive index sensor. These results show that this study provides a new idea for the design of the tunable multi-band perfect metamaterial absorber based on graphene, which has great application value in many fields and provides a new reference for future research. [ABSTRACT FROM AUTHOR]