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Chiral edge states in position shaken finite-size honeycomb optical lattice

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 نشر من قبل Xiaoji Zhou
 تاريخ النشر 2020
  مجال البحث فيزياء
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The quantum anomalies at the edges correspond to the topological phases in the system, and the chiral edge states can reflect bulk bands topological properties. In this paper, we demonstrate a simulation of Floquet systems chiral edge states in position shaken finite-size honeycomb optical lattice. Through the periodical shaking, we break the time reversal symmetry of the system, and get the topological non-trivial states with non-zero Chen number. At the topological non-trivial area, we find chiral edge states on different sides of the lattice, and the locations of chiral edge states change with the topological phase. Further, gapless boundary excitations are found to appear at the topological phase transition points. It provides a new scheme to simulate chiral edge states in the Floquet system, and promotes the study of gapless boundary excitations.



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