Design and verification of a temperature-sensitive broadband metamaterial absorber based on VO2 film

Devices based on tunable metamaterials can be used in many fields. A tunable metamaterial absorber is designed and measured based on vanadium dioxide (VO2) film. An absorption band is obtained based on superposition effect of localized surface plasmon (LSP) modes. In experiments, this absorption band can be strengthened by optimizing structural parameters radius and thickness, which are consistent with resonance properties exhibited by an LC equivalent circuit of proposed unit cells. High absorption performance can still obtain when the incident angle reaches 60°. Moreover, the absorption performance of samples can be adjusted by changing the ambient temperature in further experiments. When temperature reaches and exceeds the phase transition point, the VO2 layer exhibits an insulation-metal phase transition phenomenon, resulting in the enhancement of the absorption band.