Crosstalk-free design for the intersection of two dielectric waveguides

We propose an efficient method to reduce the crosstalk, reflection and radiation at the crossing of two dielectric waveguides in a on-chip optical interconnect network. By increasing the vertical thickness of the guides locally in the crossing region, we create better mode-matching interfaces that dramatically reduce losses. The idea is demonstrated using numerical simulations. More than 95% crosstalk power reduction and 90% reflection power reduction are observed, while the radiation power can be reduced by 40%. The method is compatible with the planar integrated circuit technique.