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Universal Hall conductance scaling in non-Hermitian Chern insulators

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 نشر من قبل Thomas Schmidt
 تاريخ النشر 2020
  مجال البحث فيزياء
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We investigate the Hall conductance of a two-dimensional Chern insulator coupled to an environment causing gain and loss. Introducing a biorthogonal linear response theory, we show that sufficiently strong gain and loss lead to a characteristic non-analytical contribution to the Hall conductance. Near its onset, this contribution exhibits a universal power-law with a power 3/2 as a function of Dirac mass, chemical potential and gain strength. Our results pave the way for the study of non-Hermitian topology in electronic transport experiments.

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