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Predicting Large-Chern-Number Phases in a Shaken Optical Dice Lattice

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 نشر من قبل Gao Xianlong
 تاريخ النشر 2020
  مجال البحث فيزياء
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With respect to the quantum anomalous Hall effect (QAHE), the detection of topological nontrivial large-Chern-number phases is an intriguing subject. Motivated by recent research on Floquet topological phases, this study proposes a periodic driving protocol to engineer large-Chern-number phases using QAHE. Herein, spinless ultracold fermionic atoms are studied in a two-dimensional optical dice lattice with nearest-neighbor hopping and a $Lambda$/V-type sublattice potential subjected to a circular driving force. Results suggest that large-Chern-number phases exist with Chern numbers equal to $C=-2$, which is consistent with the edge-state energy spectra.



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