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arXiv · 1803.03202

Multi-terminal Conductance at the Surface of a Weyl Semimetal

Jose Chesta Lopez·Luis E. F. Foa Torres·Alvaro S. Nunez
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Abstract

Weyl semimetals are a new paradigmatic topological phase of matter featuring a gapless spectrum. One of its most distinctive features is the presence of Fermi arc surface states. Here, we report on atomistic simulations of the dc conductance and quantum Hall response of a minimal Weyl semimetal. By using scattering theory we show that a quantized Hall conductance with a non-vanishing longitudinal conductance emerges associated to the Fermi arc surface states with a remarkable robustness to high concentrations of defects in the system. Additionally, we predict that a slab of a Weyl semimetal with broken time-reversal symmetry bears persistent currents fully determined by the system size and the lattice parameters.

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Jose Chesta Lopez, Luis E. F. Foa Torres, Alvaro S. Nunez. 2018-03-08. Multi-terminal Conductance at the Surface of a Weyl Semimetal. https://doi.org/10.1103/physrevb.97.125419

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