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arXiv · 2205.15123

Anomalous Transport Signatures in Weyl Semimetals with Point Defects

J. P. Santos Pires·Simão M. João·Aires Ferreira·B. Amorim·J. M. Viana Parente Lopes
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Abstract

We present the first theoretical study of transport properties of Weyl semimetals with point defects. Focusing on a class of time-reversal symmetric Weyl lattice models, we show that dilute lattice vacancies induce a finite density of quasi-localized states at and near the nodal energy, causing strong modifications to the low-energy spectrum. This generates novel transport effects, namely (i) an oscillatory behaviour of the dc-conductivity with the charge carrier density in the absence of magnetic fields, and (ii) a plateau-shaped dissipative optical response for photon frequencies below the inter-band threshold, $E_{F}\!\lesssim\!\hbar\omega\!\lesssim\!2E_{F}$.Our results provide a path to engineer unconventional quantum transport effects in Weyl semimetals by means of common point defects.

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J. P. Santos Pires, Simão M. João, Aires Ferreira, B. Amorim, J. M. Viana Parente Lopes. 2022-05-30. Anomalous Transport Signatures in Weyl Semimetals with Point Defects. https://doi.org/10.1103/physrevlett.129.196601

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