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arXiv · 1903.02000

Vanishing Hall Response of Charged Fermions in a Transverse Magnetic Field

Abstract

We study the Hall response of quasi-two-dimensional lattice systems of charged fermions under a weak transverse magnetic field, in the ballistic coherent limit. We identify a setup in which this response vanishes over a wide range of parameters: the paradigmatic "Landauer-B\"uttiker" setup commonly studied for coherent quantum transport, consisting of a strip contacted to biased ideal reservoirs of charges. We show that the effect does not rely on particle-hole symmetry, and is robust to a variety of perturbations including variations of the transverse magnetic field, chemical potential, and temperature. We trace this robustness back to a topological property of the Fermi surface: the number of Fermi points (central charge) of the system. We argue that the mechanism responsible for the vanishing Hall response can operate both in noninteracting and interacting systems, which we verify in concrete examples using density-matrix renormalization group (DMRG) simulations.

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Michele Filippone, Charles-Edouard Bardyn, Sebastian Greschner, Thierry Giamarchi. 2019-03-05. Vanishing Hall Response of Charged Fermions in a Transverse Magnetic Field. https://doi.org/10.1103/physrevlett.123.086803

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