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arXiv · 2304.08227

Dynamical properties of quasiparticles in a tunable Kekul\'{e} graphene superlattice

Xiao-Yu Xiong·Xi-Dan Hu·Qizhong Zhu·Zhi Li
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Abstract

We investigate the dynamical properties of quasiparticles in graphene superlattices with three typical Kekul\'{e} distortions (i.e., Kekul\'{e}-O, Kekul\'{e}-Y and Kekul\'{e}-M). On the one hand, we numerically show the visualized evolution process of Kekul\'{e} quasiparticles; while on the other hand, we analytically obtain the centroid trajectory of the quasiparticles, and both of them agree well with each other. The results reveal that the relativistic Zitterbewegung (ZB) phenomenon occurs in the Kekul\'{e} systems. Furthermore, through analyzing the frequency of ZB, we unveil the one-to-one relationship between ZB and Kekul\'{e} textures, i.e., the ZB frequenies of Kekul\'{e}-O, Kekul\'{e}-Y and Kekul\'{e}-M quasiparticles feature single, double and six frequencies, respectively. Finally, we propose a scheme to distinguish among different Kekul\'{e} textures from the dynamical perspective. The predictions in this paper are expected to be experimentally verified in the near future, so as to facilitate further research of Kekul\'{e} structures in solid materials or artificial systems.

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Xiao-Yu Xiong, Xi-Dan Hu, Qizhong Zhu, Zhi Li. 2023-03-20. Dynamical properties of quasiparticles in a tunable Kekul\'{e} graphene superlattice. https://doi.org/10.1016/j.physleta.2023.128957

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