Multi-spectral near perfect metamaterial absorbers using spatially multiplexed plasmon resonance metal square structures

摘要

Near perfect infrared light absorption at multi-spectral wavelengths has beenexperimentally demonstrated by using multiplexed metal square plasmon resonancestructures. Optical power absorption over 95% has been observed in dual-bandmetamaterial absorbers at two separate wavelengths and optical power absorptionover 92.5% has been observed in triple-band metamaterial absorbers at threeseparate wavelengths. The peak absorption wavelengths are primarily determinedby the sizes of the metal squares in the multiplexed structures. Electricalfield distributions in the middle of the dielectric spacer layer werecalculated at the peak absorption wavelengths. It is shown that strong lightabsorption corresponds to the local quadrupole plasmon resonance modes in themetamaterial structures.