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Characterization of symmetry-protected topological phases in polymerized models by trajectories of Majorana stars

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 نشر من قبل Shu Chen
 تاريخ النشر 2015
  مجال البحث فيزياء
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By using Majoranas stellar representation, we give a clear geometrical interpretation of the topological phases of inversion-symmetric polymerized models by mapping the Bloch states of multi-band systems to Majorana stars on the Bloch sphere. While trajectories of Majorana stars of a filled Bloch band exhibit quite different geometrical structures for topologically trivial and nontrivial phases, we further demonstrate that these structures are uniquely determined by distributions of Majorana stars of two high-symmetrical momentum states, which have different parities for topologically different states.

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