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Renormalization Group Approach to Anderson Impurity in the Bulk of Topological Insulators

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 نشر من قبل Yshai Avishai
 تاريخ النشر 2013
  مجال البحث فيزياء
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It has been recently suggested that when an Anderson impurity is immersed in the bulk of a topological insulator, a Kondo resonant peak will appear simultaneously with an in-gap bound-state when the band-dispersion has an inverted-Mexican-hat form. The mid-gap bound-state generates another spin state and the Kondo effect is thereby screened. In this paper we study this problem within a weak-coupling RG scheme where we show that the system exhibits complex crossover behavior between different symmetry configurations and may evolve into a self-screened-Kondo or SO(3) low energy fix point. Experimental consequences of this scenario are pointed out.



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