Fig. 2
The characteristics and formation mechanism of EIT resonance excited by the graphene metasurface, and the stability under various incident conditions. a, b Simulated the resonance transmission spectra (LC1 or LC2) excited by U-RCR or D-RCR alone, and the resonance transmission spectrum (EIT) excited by their combination, respectively. The inset gives the corresponding structures and polarization conditions. c, d The distribution and intensity histogram characteristics of the electric field in the x–y plane corresponding to the resonance positions of LC1, LC2, and EIT. e, f Multipolar decomposition and mode distribution of the graphene metasurface. g, h Simulated the response of graphene metasurface under non-vertical incident THz waves or different polarization angles incident THz waves. i Calculated the general figure of merit (FoM) values of EIT resonance corresponding different gap widths G2. The left blue mask is the region cannot be observed due to resonance fusion. The right yellow mask is the invalid region due to the gap width larger than the structural limit. The nonlinear fit to the data points was performed, all with R2 > 0.99.