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Degeneracy-projected polarization formulas for Hall-type conductivities

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 نشر من قبل Assa Auerbach
 تاريخ النشر 2021
  مجال البحث فيزياء
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Kubo formulas for Hall, transverse thermoelectric and thermal Hall conductivities are simplified into on-shell commutators of degeneracy projected polarizations. The new expressions are computationally economical, and apply to general Hamiltonians without a gap restriction. We show that Hall currents in open boundaries are carried by gapless chiral excitations. Extrapolation of finite lattice calculations to the DC-thermodynamic limit is demonstrated for a disordered metal.



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