Design and verification of a single band metasurface based on cross-shaped metal array

Abstract

A single-band terahertz (THz) high performance metasurface absorber is designed and verified based on the ohmic loss of the cross-shaped metal array. In the first set of experiments, three samples with structural parameters w=2.4μm, w=3.8μm, and w=4.2μm are prepared and measured. The absorption peak is enhanced from 80.2% to 96.8%, and the resonance frequency is reduced from 35.96 THz to 31.06 THz. In the second set of experiments, three other samples with structural parameters L=8.0μm, L=8.4μm, and L=8.8μm are prepared and measured (other structural parameters remained unchanged, and the test conditions remained unchanged). The absorption peak is increased from 80.2% to 88.8%, and resonance frequency is shifted to 27.28 THz. In the third set of experiments, samples with structural parameters w=2.4μm are placed in three different gases. Three high sensitivities are achieved by this samples: SNO=1421Hz/RIU, SCO=1674Hz/RIU, and SCO2=1897Hz/RIU. This proposed metasurface absorber shows the potential in gas sensing.

Keywords

• Metasurface
• Sensor
• Absorptivity