Fig. 1. Structural drawing. (a) Three-dimensional view of metamaterials; (b) side view; (c) front view

Fig. 2. EIT spectrogram of three structures

Fig. 3. Electromagnetic field distribution diagrams at each resonance peak of EIT. (a)--(d) Electric field distribution diagrams; (e)--(h) magnetic field distribution diagrams

Fig. 4. Comparison of positive and negative split rings with structures I and II. (a) Forward double split ring; (b) reverse double split ring; (c) electromagnetic field distribution of separate structure

Fig. 5. Effect of opening size on EIT effect

Fig. 6. Influence of closed square ring size on EIT effect

Fig. 7. Spectrogram of slow light effect at multiple frequencies. (a) S parameter; (b) group refractive index and refractive index change with frequency

Fig. 8. Multi-band refractive index sensing spectrogram. (a) EIT curves at different refractive indices; (b) refractive index sensitivity in four bands