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Can 1D topological states explain the extraordinary thermoelectric properties of Bi 2 Te 3 ? An exact analytical solution in the Tomonaga-Luttinger liquids (TLLs) framework

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 نشر من قبل Piotr Chudzinski
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف P.Chudzinski




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Topological insulators are frequently also one of the best known thermoelectric materials. It has been recently discovered that in 3D topological insulators each skew dislocation can host a pair of 1D topological states a helical TLL. We derive exact analytical formulas for thermoelectric Seebeck coefficient in TLL and investigate up to what extent one can ascribe the outstanding thermoelectric properties of Bi 2 Te 3 to these 1D topological states. To this end we take a model of a dense dislocation network and find an analytic formula for an overlap between 1D (the TLL) and 3D electronic states. Our study is applicable to a weakly n-doped Bi 2 Te 3 but also to a broader class of nano-structured materials with artificially created 1D systems. Furthermore, our results can be used at finite frequency settings e.g. to capture transport activated by photo-excitations.



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