One-way rotating state of multi-periodicity frequency bands in circular photonic crystal

The one-way rotating state is realized in circular photonic crystal (CPC) with yttrium-iron-garnet rods. Adopting 5 ring rods, eight one-way rotating mode frequency bands with periodic distribution and their corresponding eight one-way rotating resonant modes are found within a specific frequency range and their distribution laws are obtained. Adopting 2-6 ring rods, the best bandwidth and localization for the one-way rotating state are realized, respectively, when adopting 4 and 6 ring rods. The research results will provide reference for the designs of the new one-way rotating state devices based on CPC.