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Quantized Nonlinear Conductance in Ballistic Metals

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 نشر من قبل Charles Kane
 تاريخ النشر 2021
  مجال البحث فيزياء
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 تأليف C. L. Kane




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We introduce a non-linear frequency dependent D+1 terminal conductance that characterizes a D dimensional Fermi gas, generalizing the Landauer conductance in D=1. For a ballistic conductor we show that this conductance is quantized and probes the Euler characteristic of the Fermi sea. We critically address the roles of electrical contacts and of Fermi liquid interactions, and we propose experiments on 2D Dirac materials such as graphene using a triple point contact geometry.



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