Low loss 100 GHz spacing Si arrayed-waveguide grating using minimal terrace at slab–array interface

Si wire arrayed-waveguide grating is reported using local rib waveguide generating multimode interference at the array and slab waveguide interface. An 8ch device with 100 GHz channel spacing showing 1.2 dB insertion loss is obtained. A loss improvement near the theory was attained using minimum terrace area compared with a device using simple width taper.