Universality, exponents and anomaly cancellation in disordered Dirac fermions

Vieri Mastropietro

doi:10.1016/j.nuclphysb.2013.07.007

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arXiv · 1306.4023

Universality, exponents and anomaly cancellation in disordered Dirac fermions

Vieri Mastropietro

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Abstract

Disordered 2D chiral fermions provide an effective description of several materials including graphene and topological insulators. While previous analysis considered delta correlated disorder and no ultraviolet cut-offs, we consider here the effect of short range correlated disorder and the presence of a momentum cut-off, providing a more realistic description of condensed matter models. We show that the density of states is anomalous with a critical exponent function of the disorder and that conductivity is universal only when the ultraviolet cut-off is removed, as consequence of the supersymmetric cancellation of the anomalies.

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Vieri Mastropietro. 2013-06-17. Universality, exponents and anomaly cancellation in disordered Dirac fermions. https://doi.org/10.1016/j.nuclphysb.2013.07.007

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