Slow light with high normalized delay-bandwidth product in organic photonic crystal coupled-cavity waveguide

In this theoretical study, a photonic crystal coupled-cavity waveguide created on polymer substrate was demonstrated to provide high-performance slow light with low group-velocity dispersion and large normalized delay-bandwidth product. Combined with structural-parameter optimization, the normalized delay-bandwidth product was enhanced to a large value of 0.809, and the group-velocity dispersion was on the order of 10⁴(ps²/km). Furthermore, the optimized coupled-cavity waveguide had tunability capabilities by changing the external pump laser power. Importantly, while adjusting the slow light, the normalized delay-bandwidth product values remained above 0.8, which was necessary to maintain the performance of optical buffering devices.