Flat-top silica-based arrayed waveguide grating with 40-channels

A flat response silica-based arrayed waveguide grating (AWG) with 40-channels and 0.8 nm (100 GHz) channel spacing has been designed and fabricated using multimode interferometer (MMI) at the end of input waveguide. Proper width of MMI is theoretically optimized using beam propagation method (BPM). An AWG with a 16 μm width MMI is fabricated experimentally. The measurement results show that the 3 dB bandwidth is 0.62 nm, insertion loss (IS) ranges from 5.2 dB to 7.5 dB, and the crosstalk is less than —20 dB. The 3dB bandwidth, channel numbers and channel spacing of the AWG agree well with the simulation values. Supported by the National Natural Science Foundation of China (No. 60477035, No. 60507006) and The Ministry of Science and Technology “973” Plan (No. G2000036602)