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arXiv · 1512.07164

Disordered double Weyl node

Björn Sbierski·Maximilian Trescher·Emil J. Bergholtz·Piet W. Brouwer
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Abstract

Double Weyl nodes are topologically protected band crossing points which carry chiral charge $\pm2$. They are stabilized by $C_4$ point group symmetry and are predicted to occur in $\mathrm{SrSi_2}$ or $\mathrm{HgCr_{2}Se_{4}}$. We study their fate in the presence of quenched disorder by numerical transport calculations and scaling arguments. We find that a double Weyl node is unstable in a disordered environment and splits into a pair of emergent simple Weyl nodes which carry equal chiral charge of $\pm1$. This pair of simple Weyl nodes is robust to disorder up to a certain critical disorder strength, in complete analogy to their `elementary' counterparts.

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Björn Sbierski, Maximilian Trescher, Emil J. Bergholtz, Piet W. Brouwer. 2016-04-06. Disordered double Weyl node. https://doi.org/10.1103/physrevb.95.115104

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