Optimized silicon AWG with flattened spectral response using an MMI aperture

We demonstrate compact 12-channel 400 GHz arrayed waveguide grating wavelength demultiplexers (AWG) in silicon with a flattened spectral response. Insertion loss, crosstalk and non-uniformity are -3.29 dB, 17.0 dB and 1.55 dB, respectively. The flattened spectral response is obtained by using an optimized mode shaper consisting of a multi-mode interference coupler as the input aperture of the AWG. The ratio of the 1 dB bandwidth to the 10 dB bandwidth is improved by 50%, from 0.33 to 0.49 compared to a conventional AWG. The device size is only 560x350 mu m(2)