Fig. 1. (a) The metasurface array of double parallel nanorods with different lengths. (b) The planar graph of this structure

Fig. 2. The interactive electric energy between the moment of the double nanorods’ dipole

Fig. 3. Transmittance spectra of the nanorod dimer nanostructures, where the distances of the short nanorod’s center deviating from the long nanorod’s center is fixed as 0 nm and 80 nm

Fig. 4. The distribution of the normalized square of the electric field (|E|²) and the charge density of the nanorod dimer for the symmetry structure peak at A and C, and dip at B and D where S = 0 nm at (a) λ_A = 2.32 μm, (b) λ_B = 2.36 μm, (c) λ_C = 2.92 μm, and (d) λ_D = 3.00 μm

Fig. 5. The distribution of the normalized square of electric field (|E|²) and the charge density of the double parallel nanorods for symmetry structure at the peak E, G, I and dips F, H, J with the parameter s = 80 nm at λ_E = 2.26 mm (a), λ_F = 2.30 mm (b), λ_G = 2.36 mm (c), λ_H = 2.90 mm (d), λ_I = 2.98 mm (e), and λ_J = 3.00 mm (f).

Fig. 6. Transmission spectra of the double parallel nanorods: (a) s = 0, 20, 40, 60, and 80 nm with fixed L₂ = 800 nm, w = 100 nm, L₁ = 400 nm, t = 50 nm and g = 20 nm. (b) L₁ = 400, 420, 440, 460, and 480 nm with fixed S = 0 nm, w = 100 nm, L₂ = 800 nm, t = 50 nm and g = 20 nm.

Fig. 7. Transmission spectra of the double parallel nanorods. (a) g = 20, 40, 60, 80, 100 nm with fixed s = 0 nm, L₁ = 400 nm, w = 100 nm, L₂ = 800 nm and t = 50 nm. (b) θ = 0°, 30°, 60°, and 90° with fixed s = 0 nm, L₁ = 400 nm, w = 100 nm, L₂ = 800 nm, t = 50 nm, and g = 20 nm

Fig. 8. (a) Transmission spectra varying with different refractive index n. (b) Relationship between the resonance dip wavelength λ₁ and λ₂ and the refractive index. (c) Relationship between resonance dip wavelength change δλ and the change in the refractive index δn