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arXiv · 1611.08125

Axial Hall effect and universality of holographic Weyl semi-metals

Christian Copetti·Jorge Fernández-Pendás·Karl Landsteiner
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Abstract

The holographic Weyl semimetal is a model of a strongly coupled topological semi-metal. A topological quantum phase transition separates a topological phase with non-vanishing anomalous Hall conductivity from a trivial state. We investigate how this phase transition depends on the parameters of the scalar potential (mass and quartic self coupling) finding that the quantum phase transition persists for a large region in parameter space. We then compute the axial Hall conductivity. The algebraic structure of the axial anomaly predicts it to be 1/3 of the electric Hall conductivity. We find that this holds once a non-trivial renormalization effect on the external axial gauge fields is taken into account. Finally we show that the phase transition also occurs in a top-down model based on a consistent truncation of type IIB supergravity.

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Christian Copetti, Jorge Fernández-Pendás, Karl Landsteiner. 2017-02-22. Axial Hall effect and universality of holographic Weyl semi-metals. https://doi.org/10.1007/jhep02(2017)138

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