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arXiv · 2404.16937

No bulk thermal currents in massive Dirac fermions

Feng Liu·A. Daria Dumitriu-I.·Alessandro Principi
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Abstract

We calculate the energy current flowing in the bulk of a (2+1)-dimensional system of massive Dirac fermions and along a (1+1)-dimensional domain wall generated by flipping the sign of the particle mass. We show that, at low temperatures and in the long-wavelenghth limit, the system does not support a bulk thermal Hall current proportional to the temperature gradient. The only such contribution is due to states localised at the domain wall. This puts an end to a controversy existing in the literature and amends previous results obtained via first-order perturbation calculations.

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Feng Liu, A. Daria Dumitriu-I., Alessandro Principi. 2024-04-25. No bulk thermal currents in massive Dirac fermions. https://arxiv.org/abs/2404.16937

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