Spectral characteristics of coupled resonators

In devices consisting of a large number of coupled resonators, the coupling coefficients are unlikely to be identical throughout the ensemble, owing to statistical fluctuations in the fabrication process, the surrounding environment, or the device operation process. We describe how the frequency spectrum of such a disordered device differs from that of earlier models that assume a perfectly ordered lattice of resonant elements. Based on simulations for a large number of nominally identical resonators perturbed by disorder in the coupling coefficients, we describe the change in the density of modes (resonances) using both Hermitian and non-Hermitian coupling pathways, following recent experimental demonstrations. The band-edge zero-group-velocity state is highly sensitive to disorder, and applications that rely on band-edge effects, such as ultraslow light and group-velocity dispersion compensation, may be strongly impacted. (c) 2006 Optical Society of America.