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arXiv · 1709.10133

Mirror Anomaly in Dirac Semimetals

A. A. Burkov
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Abstract

We demonstrate that, apart from the chiral anomaly, Dirac semimetals possess another quantum anomaly, which we call the mirror anomaly, and which manifests in a singular response of the Dirac semimetal to an applied magnetic field. Namely, the anomalous Hall conductivity exhibits step-function singularities when the field is rotated. We show that this phenomenon is closely analogous to the parity anomaly of (2+1)-dimensional Dirac fermions, but with mirror symmetry, which we demonstrate emerges near any Dirac point at a time reversal invariant momentum, replacing the parity symmetry.

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A. A. Burkov. 2018-01-05. Mirror Anomaly in Dirac Semimetals. https://doi.org/10.1103/physrevlett.120.016603

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