Fig. 1. Metamaterial element structure. (a) Top view; (b) left view; (c) front view

Fig. 2. Transmission spectrum and fitting curve of metamaterials. (a) Transmission spectrum; (b) fitting curve

Fig. 3. Study on intrinsic physical mechanism of Fano resonance in metamaterials. (a) Current density distribution of metamaterials; (b) schematic diagram of toroidal dipole excitation; (c) electric field distribution of metamaterials; (d) scattering powers of different types of multipole

Fig. 4. Influence of spacing g on Q value. (a) g=5 nm; (b) g=10 nm; (c) g=20 nm; (d) g=40 nm

Fig. 5. Schematic diagram of double harmonic oscillator model

Fig. 6. Harmonic oscillator amplitude

Fig. 7. Influence of g on FOM

Fig. 8. Influence of L_y on Q value and transmittance. (a) Q value; (b) transmittance

Fig. 9. Influence of detector thickness on TD resonance wavelength shift

Fig. 10. Electric field distributions of metamaterials under different h_a. (a) h_a=0; (b) h_a=50 nm; (c) h_a=100 nm; (d) h_a=400 nm

Fig. 11. Influence of n_a on transmission spectra and resonance wavelength shift. (a) Transmission spectra; (b) resonance wavelength shift