Manipulation of topological antichiral edge states by inducing valley-chirality coupling.

Benefiting from the non-uniform assigning on the sublattices A and B in a modified Haldane model, the reductions of both spatial inversion and time-reversal symmetries can be induced to implement the competition of valley and chirality, which provide us a new, to the best of our knowledge, means to manipulate the topological antichiral edge states (ACEs). An implementation method for harnessing ACEs in a two-dimensional gyromagnetic photonic crystal (PC) has been proposed, which reveals that the opposite magnetization applied in the cylinders of sublattices A and B can generate the ACEs, and the valley Hall phase induced by dimerization of the structure further manipulates the edge states. Moreover, we found that the one-way dual transport channels of the ACEs can be transformed from both upper and lower zigzag edges into only one channel due to the propagating direction mismatched in the gyromagnetic PC heterojunction structure. Our research enriches the understanding of antichiral one-way transport states and offers useful insights and routines to design novel topological electromagnetic and optical functional devices.