Fig. 1. Illustration of unit cell of metamaterial. (a) Metamaterial structure with two metal layers; (b) metamaterial structure with single metal layer

Fig. 2. Spectra under different polarizations. (a) TM polarization, S11, S21; (b) TM polarization, μ; (c) TE polarization, S11, S21; (d) TE polarization, μ

Fig. 3. Current distributions on metal surface under TM polarization. (a) f=0.924 THz; (b) f=1.44 THz; (c) f=2.1 THz

Fig. 4. Spectra under different polarizations. (a) TM polarization, S21; (b) TM polarization, real part of μ; (c) TE polarization, S21; (d) TE polarization, real part of μ

Fig. 5. Spectra under TM polarization and different metal layer numbers. (a) S11; (b) S21; (c) real part of μ

Fig. 6. Spectra under different polarizations and dielectric layer thicknesses. (a) TM polarization, S21; (b) TM polarization, real part of μ; (c) TE polarization, S21; (d) TE polarization, real part of μ

Fig. 7. Schematics under different polarizations and tolerance error percentages. (a) TM polarization, S21 spectra; (b) TM polarization, real part of μ; (c) TM polarization, near-zero bandwidth; (d) TE polarization, S21 spectra; (e) TE polarization, real part of μ; (f) TE polarization, near-zero bandwidth

Fig. 8. Spectra under TM polarization and different incident angles. (a) S21; (b) real part of μ