Fig. 1. Schematic of the proposed device based on triple-ring-assisted MZI

Fig. 2. The influence of ρ_A and ρ_B on the performance of the optical filter

Fig. 3. Normalized central frequency is shifted with the change of the extra phase θ applied on the three resonators

Fig. 4. The structure of the race-track microring resonator

Fig. 5. The value of ρ_Amin with different W_idth， G_ap and L_nA

Fig. 6. The relationship between the FSR and the minimum SER of the two outputs

Fig. 7. The relationship between the initial phase and Δn

Fig. 8. The structure of the phase shifter

Fig. 9. The performance of the optical filter with different θ_B and θ_C

Fig. 10. The reconfigurations of the wavelength and the bandwidth of the filter