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arXiv · 1712.03635

Magnetoconductivity of type-II Weyl semimetals

Yi-Wen Wei·Chao-Kai Li·Jingshan Qi·Ji Feng
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Abstract

Type-II Weyl semimetals are characterized by the tilted linear dispersion in the low-energy excitations, mimicking Weyl fermions but with manifest violation of the Lorentz invariance, which has intriguing quantum transport properties. The magnetoconductivity of type-II Weyl semimetals is investigated numerically based on lattice models in parallel electric and magnetic field. We show that in the high-field regime, the sign of the magnetoconductivity of an inversion-symmetry-breaking type-II Weyl semimetals depends on the direction of the magnetic field, whereas in the weak field regime, positive magnetoconductivity is always obtained regardless of magnetic field direction. We find that the weak localization is sensitive to the spatial extent of impurity potential. In time-reversal symmetry breaking type-II Weyl semimetals, the system displays either positive or negative magnetoconductivity along the direction of band tilting, owing to the associated effect of group velocity, Berry curvature and the magnetic field.

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Yi-Wen Wei, Chao-Kai Li, Jingshan Qi, Ji Feng. 2017-12-11. Magnetoconductivity of type-II Weyl semimetals. https://doi.org/10.1103/physrevb.97.205131

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