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arXiv · 1612.00486

AC conductivity for a holographic Weyl Semimetal

Gianluca Grignani·Andrea Marini·Francisco Pena-Benitez·Stefano Speziali
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Abstract

We study the AC electrical conductivity at zero temperature in a holographic model for a Weyl semimetal. At small frequencies we observe a linear dependence in the frequency. The model shows a quantum phase transition between a topological semimetal (Weyl semimetal phase) with a non vanishing anomalous Hall conductivity and a trivial semimetal. The AC conductivity has an intermediate scaling due to the presence of a quantum critical region in the phase diagram of the system. The phase diagram is reconstructed using the scaling properties of the conductivity. We compare with the experimental data of [1502.03807] obtaining qualitative agreement.

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Gianluca Grignani, Andrea Marini, Francisco Pena-Benitez, Stefano Speziali. 2017-03-20. AC conductivity for a holographic Weyl Semimetal. https://doi.org/10.1007/jhep03(2017)125

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