Collective states with high quality factors in chains of dielectric resonators

Coupled dielectric subwavelength resonators supporting collective states with high quality factors are of interest due to potential in the enhancement of the light-matter interaction at the nanoscale and high versatility and tunability of such structures. Recently, it was theoretically shown that coupling between two or more collective modes via radiation continuum that can occur under variation of the parameters of such structures could significantly boost the quality factor of one of the eigenmodes. In this work, we have studied such effect numerically and experimentally for a chain of ceramic cylinders operating in the microwave spectral range. We have investigated how the present channels of losses, namely material losses, and additional scattering due to variation in geometrical and materials parameters, influence the considered effect. We have developed a feasible design that allows for observation of mode interaction.
Experimental measurements of the spectral response of the proposed structures confirmed the main predicted results.