Enhancing the guiding bandwidth of photonic crystal waveguides on silicon-on-insulator.

In this work we present a systematic approach to increase the low-loss guiding bandwidth of PCWs by reducing the interaction of low-group-velocity modes with the surrounding photonic crystal. By this method the low-loss bandwidth of a W1 PCW is increased from 2.5 nm to 12 nm. We also present a detailed analysis of the transmission properties of W1 PCWs and elaborate on the coupling to TM-like guided modes present in the low-loss transmission bandwidth of this device.