Simulation and fabrication of a single-band tunable absorber in 20–50 THz range based on cross array metamaterials

Abstract

In this paper, a tunable metamaterial is designed and measured in the 20–50 THz band. An absorption peak (80%) is obtained at resonance frequency point 40THz based on the LSP mode resonance on the surface of metal array and the dielectric loss mode in two dielectric layers. In experiments, the amplitude is increased and the resonance frequency is reduced through decreasing the lattice constant P or increasing the side length W1. In the third and fourth sets of experiments, this absorption peak can be controlled through increasing or reducing the temperature. This is due to the insulator-metal or metal-insulator phase transitions are achieved. Moreover, under the room temperature 300 K and normal pressure, the absorption amplitudes are enhanced and the resonance frequency is shifted with different liquid layers. This sample shows the feasibility of application to temperature or liquid sensing.