Fig. 1. The three-level model of electromagnetically induced transparency

Fig. 2. Coupled resonant waveguide structure to realize EIT effect

Fig. 3. Transmission spectrum of EIT

Fig. 4. The Ez distribution corresponding to the frequency at each transmission peak （dip）

Fig. 5. The Ez distribution corresponding to the frequency on both sides of each transmission peak （dip）

Fig. 6. The effect of coupling distance on EIT effect