1D periodic structures for slow-wave induced non-linearity enhancement.

A comparison between several 1D periodic structures designed to enhance non-linear effects for high-speed all-optical applications is presented. These structures allow for a small group velocity of the propagating waves, so the light-matter interaction is increased, making the non-linear process to be more efficient. In addition, the propagating wave is compressed, making the field intensity to be higher in the non-linear material. Thus, a significant reduction in both the structure length and the input power needed to induce a particular phase shift is achieved. The selected 1D periodic structures are compared by means of properties such as the modal effective volume, coupling efficiency, mode bandwidth, group velocity dispersion, and easiness of fabrication, in order to determine the optimum configuration in terms of non-linear enhancement.