Frequency-dependent spatial regulation of chiral and antichial edge states in photonic crystals under sublattice modulation

The chiral edge states in the Haldane model and the antichiral edge states in the modified Haldane model have been extensively studied, revealing intriguing transport properties. In this work, the frequency-dependent spatial regulation of chiral and antichial edge states is investigated in the gyromagnetic photonic crystals through sublattice modulation. The unequal magnetization intensity on two-type sublattices, breaking the inversion symmetries, leads to the shift of the chiral edge state dispersions and the lift of the degenerate antichiral edge states. Through simulations and experiments, we demonstrate that under sublattice modulation, the transport efficiency of chiral and antichial edge states at different edges is actively controlled, breaking through the functional limitations of conventional models. Based on this mechanism, a multi-channel waveguide is proposed, providing a new path for the functional innovation and system integration of topological photonic devices.