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arXiv · 2304.08227

Dynamical properties of quasiparticles in a tunable Kekulé graphene superlattice

Abstract

We investigate the dynamical properties of quasiparticles in graphene superlattices with three typical Kekulé distortions (i.e., Kekulé-O, Kekulé-Y and Kekulé-M). On the one hand, we numerically show the visualized evolution process of Kekulé 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 Kekulé systems. Furthermore, through analyzing the frequency of ZB, we unveil the one-to-one relationship between ZB and Kekulé textures, i.e., the ZB frequenies of Kekulé-O, Kekulé-Y and Kekulé-M quasiparticles feature single, double and six frequencies, respectively. Finally, we propose a scheme to distinguish among different Kekulé 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 Kekulé 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 Kekulé graphene superlattice. https://doi.org/10.1016/j.physleta.2023.128957

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