Fig. 1. The schematic structure of the AWG

Fig. 2. Variation of mode effective refractive index with waveguide width

Fig. 3. (a) Simulated mode field propagation at 6 µm spacing； (b) Simulated mode field propagation at 8 µm spacing

Fig. 4. (a)The top view of a parabolic taper； (b) Parabolic tapered waveguide transmission field

Fig. 5. (a)Spectra corresponding to different output waveguide widths；(b) Simulated mode field propagation at 14 µm spacing

Fig. 6. The schematic of 16-channel AWG

Fig. 7. The schematic diagram of the 16-channel AWG fabrication process

Fig. 8. (a) The photograph of the manufactured AWG chip； (b) the microscope image of the manufactured AWG chip, and (c) the photograph of the packaged 16-channel AWG module

Fig. 9. (a) The experimental setup for testing spectral response；(b) The measured spectral response

Fig. 10. （a）insertion loss for each channel； （b）polarization-dependent loss； （c）crosstalk；（d）ripple；（e）offset； （f）bandwidth

Fig. 11. (a) Experimental setup for testing eye diagrams and (b) the measured 53.125 GBaud PAM4 optical eye diagrams for all channels