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arXiv · 1210.6121

Stability of Weyl metals under impurity scattering

Zhoushen Huang·Tanmoy Das·Alexander V. Balatsky·Daniel P. Arovas
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Abstract

We investigate the effects of bulk impurities on the electronic spectrum of Weyl semimetals, a recently identified class of Dirac-type materials. Using a $T$-matrix approach, we study resonant scattering due to a localized impurity in tight binding versions of the continuum models recently discussed by Burkov, Hook, and Balents, describing perturbed four-component Dirac fermions in the vicinity of a critical point. The impurity potential is described by a strength $g$ as well as a matrix structure $\Lambda$. Unlike the case in d-wave superconductors, where a zero energy resonance can always be induced by varying the impurity scalar and/or magnetic impurity strength, we find that for certain types of impurity ($\Lambda$), the Weyl node is protected, and that a scalar impurity will induce an intragap resonance over a wide range of scattering strength. A general framework is developed to address this question, as well as to determine the dependence of resonance energy on the impurity strength.

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Zhoushen Huang, Tanmoy Das, Alexander V. Balatsky, Daniel P. Arovas. 2012-10-23. Stability of Weyl metals under impurity scattering. https://doi.org/10.1103/physrevb.87.155123

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