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arXiv · 2108.03607

Anti-chiral edge states and hinge states based on the Haldane model

Abstract

Different from the chiral edge states, antichiral edge states propagating in the same direction on the opposite edges are theoretically proposed based on the modified Haldane model, which is recently experimentally realized in photonic crystal and electric lattice systems. Here, we instead present that the antichiral edge states in the two-dimensional system can also be achieved based on the original Haldane model by combining two subsystems with the opposite chirality. Most importantly, by stacking these two-dimensional systems into three-dimension, it is found that the copropagating antichiral hinge states localized on the two opposite diagonal hinge cases of the system can be implemented. Interestingly, the location of antichiral hinge states can be tuned via hopping parameters along the third dimension. By investigating the local Chern number/layer Chern number and transmission against random disorders, we confirm that the proposed antichiral edge states and hinge states are topologically protected and robust against disorders. Our proposed model systems are expected to be realized in photonic crystal and electric lattice systems.

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Xiaoyu Cheng, Jun Chen, Lei Zhang, Liantuan Xiao, Suotang Jia. 2021-08-08. Anti-chiral edge states and hinge states based on the Haldane model. https://doi.org/10.1103/physrevb.104.l081401

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