摘要
One-dimensional(1D)one-way waveguides based on topological edge states of two-dimensional(2D)gyromagnetic photonic crystals have been studied extensively.Here,we theoretically propose a three-dimensional(3D)all-dielectric gyromagnetic photonic crystal with type-Ⅱ Weyl points.Based on the inclined band properties of the type-Ⅱ Weyl surface states,we design a 2D one-way interface transmission channel on the Weyl crystal.Light waves in such 2D waveguides can be transmitted robustly over metal obstacles almost without any back-reflection,topologically protected by the type-Ⅱ Weyl points.By manipulating the magnetic field or structural parameters,we also achieve the topological phase transition between Weyl phase and 3D Chern insulator phase and obtain the corresponding phase diagram,which provides more possibilities for topological regulation of the surface states.This work suggests a new way to construct unidirectional 2D waveguides with larger area of energy transmission in 3D space,which is a promising platform for developing 3D topological photonic devices.
基金
supported by the National Natural Science Foundation of China(Grant No.11974119)
Science and Technology Project of Guangdong(Grant No.2020B010190001)
Guangdong Innovative and Entrepreneurial Research Team Program(Grant No.2016ZT06C594)
National Key R&D Program of China(Grant No.2018YFA0306200)。