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Spin-textured Chern bands in AB-stacked transition metal dichalcogenide bilayers

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 نشر من قبل Yang Zhang
 تاريخ النشر 2021
  مجال البحث فيزياء
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While transition metal dichalcogenide (TMD) based moire materials have been shown to host various correlated electronic phenomena, topological states have not been experimentally observed until now. In this work, using first principles calculations and continuum modeling, we reveal the displacement field induced topological moire bands in AB-stacked TMD heterobilayer MoTe2/WSe2. Valley contrasting Chern bands with non-trivial spin texture are formed from interlayer hybridization between MoTe2 and WSe2 bands of nominally opposite spins. Our study establishes a recipe for creating topological bands in AB stacked TMD bilayers in general, which provides a highly tunable platform for realizing quantum spin Hall and interaction induced quantum anomalous Hall effects.



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