Fig. 1. Schematic diagram of the designed add-drop filter

Fig. 2. Schematic of corrugation distribution of different grating assisted contra-DCs

Fig. 3. Calculated effective indices of the TE₀ modes with the phase-match condition

Fig. 4. Calculated electric field distributions of TE₀ mode

Fig. 5. Calculated coupling coefficient varies with ΔW_A

Fig. 6. Calculated variation of coupling coefficient κ and lateral-misalignment ΔL with the number of grating periods under different apodization coefficients

Fig. 7. Calculated spectral responses of the uniform and conventional lateral-misalignment modulation contra-DCs

Fig. 8. Calculated spectral response of the conventional lateral-misalignment modulation contra-DC under different apodization coefficients

Fig. 9. The calculated spectra of complementary lateral- misalignment modulation contra-DC and spectrum comparison of the drop port with and without complementary lateral- misalignment modulation contra-DCs

Fig. 10. Calculated drop port spectral responses of complementary lateral-misalignment modulation contra-DCs under different apodization coefficients