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Quantum Hall effective action for anisotropic Dirac semi-metal

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 نشر من قبل Piotr Surowka
 تاريخ النشر 2020
  مجال البحث فيزياء
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We present a study of Hall transport in semi-Dirac critical phases. The construction is based on a covariant formulation of relativistic systems with spatial anisotropy. Geometric data together with external electromagnetic fields is used to devise an expansion procedure that leads to a low-energy effective action consistent with the discrete $PT$ symmetry that we impose. We use the action to discuss terms contributing to the Hall transport and extract the coefficients. We also discuss the associated scaling symmetry.

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