SOI-based compact mode- and polarization-division multiplexer for on-chip optical interconnects: design and simulation.

A compact seven-channel hybrid mode- and polarization-division multiplexer based on a silicon-on-insulator (SOI) waveguide platform is proposed for on-chip optical interconnects. Three independent signals are coupled into the , , and mode of a three moded waveguide using a taper, a polarization beam splitter, and an asymmetric directional coupler in the first coupler section. In the adiabatically connected second and third sections, two collocated asymmetric directional couplers are used to couple two TE modes (, ) and two TM modes (, ) to reduce the footprint of the device. A coupling length of ∼44.29µ is achieved with low insertion loss <0.09 and crosstalk better than -30 at the designed wavelength of 1.55 µm.