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arXiv · 2108.11372

Degeneracy-projected polarization formulas for Hall-type conductivities

Noga Bashan·Assa Auerbach
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Abstract

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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Noga Bashan, Assa Auerbach. 2022-01-11. Degeneracy-projected polarization formulas for Hall-type conductivities. https://doi.org/10.1103/physrevlett.128.036601

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