Title: Ultra-wide-band slow light in photonic crystal coupled-cavity waveguides,
Abstract: Slow light propagation in structured materials is a highly promising approach
for realizing on-chip integrated photonic devices based on enhanced optical
nonlinearities. One of the most successful research avenues consists in
engineering the band dispersion of light-guiding photonic crystal (PC)
structures. The primary goal of such devices is to achieve slow-light operation
over the largest possible bandwidth, with large group index, minimal index
dispersion, and constant transmission spectrum. Here, we report on the
experimental demonstration of to date record high GBP in silicon-based
coupled-cavity waveguides (CCWs) operating at telecom wavelengths. Our results
rely on novel CCW designs, optimized using a genetic algorithm, and refined
nanofabrication processes.