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Topological non-symmorphic crystalline insulators

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 نشر من قبل Chao-xing Liu
 تاريخ النشر 2013
  مجال البحث فيزياء
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In this work, we identify a new class of Z2 topological insulator protected by non-symmorphic crystalline symmetry, dubbed a topological non-symmorphic crystalline insulator. We construct a concrete tight-binding model with the non-symmorphic space group pmg and confirm the topological nature of this model by calculating topological surface states and defining a Z2 topological invariant. Based on the projective representation theory, we extend our discussion to other non-symmorphic space groups that allows to host topological non-symmorphic crystalline insulators.

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