Fig. 1. Fabrication and characterization of LIG. (a) Schematic of LIG fabrication; (b) Raman spectrograms of LIG and PI; (c) SEM image of the fabricated LIG; (d) cross-sectional SEM image of the fabricated LIG

Fig. 2. Relationship between laser processing parameters and LIG conductivity. (a) Laser-power-dependent electrical conductivity of the LIG at different laser scanning speeds; (b) laser-scanning-speed-dependent electrical conductivity of the LIG at different laser powers

Fig. 3. Terahertz LIG metamaterial filter. (a) Schematic diagram of terahertz LIG metamaterial filter structure; (b) experimental and simulated terahertz transmission spectra at U=300, 400 and 500 μm; (c) corresponding optical micrographs

Fig. 4. Polarization characteristics of terahertz LIG metamaterial filter. (a) Experimental results; (b) simulation results; (c) filter transmission spectra under different θ at 0.55 THz; (d) distribution of electric field on the surface of corresponding metamaterial filter