Dynamic Light Storage in Slow Light Waveguides

An approach to store light dynamically in slow light waveguides is proposed. First, design guidelines are developed for waveguides that allow dynamic group velocity control. Then an example of a silicon photonic crystal waveguide is presented where group velocity can be drastically reduced by applying a refractive index change of -5.5×10^-2 to a specific part of the waveguide. Performing the index change while a light pulse is confined to the waveguide, we show by numerical simulations a tunable storage time of more than 70 ps for a pulse of 60 GHz bandwidth. We argue that the magnitude of the required change of the refractive index can be reduced by mode optimization.