RESUMEN
Topological rainbows (TRs) possess the potential to separate and localize topological photonic states across different frequencies. However, previous works on TRs have been confined to a single-frequency band. Furthermore, the achievement of multiband TRs within a single structure is still a significant challenge. In this paper, a composed structure waveguide is designed based on Penrose-triangle photonic crystals. By adjusting the size of scatterers and introducing non-Hermitian terms, we successfully realize dual-band TRs. This achievement will not only enhance the uniformity of the electric field intensity distribution but also provide the potential to introduce a new avenue for the development of robust photonic devices dedicated to processing vast amounts of data information.
RESUMEN
The topological edge state (TES) and topological corner state (TCS) in photonic crystals (PCs) provide effective ways to manipulate the propagation of light. To improve the performance and integration of topological photonic devices, the realization of multiband topological states by PCs combined with quasi-periodic structure needs to be urgently explored. In this Letter, a Penrose-triangle (P-T) PC, which arranges the basic structural unit of a 12-fold Penrose-type photonic quasi-crystal (PQC) in a triangular lattice, is proposed. The TES and TCS at low- and high-frequency bands can be generated in the same structure, accompanied by the realization of three groups of TCSs. This will provide a new structure for the generation of TESs and TCSs in PCs, and will provide a new way to improve the performance and integration of topological photonic devices.
