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arXiv · 1809.08601

Weyl semimetal/insulator transition from holography

Yan Liu·Junkun Zhao
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Abstract

We study a holographic model which exhibits a quantum phase transition from the strongly interacting Weyl semimetal phase to an insulating phase. In the holographic insulating phase there is a hard gap in the real part of frequency dependent diagonal conductivities. However, the anomalous Hall conductivity is nonzero at zero frequency, indicting that it is a Chern insulator. This holographic quantum phase transition is always of first order, signified by a discontinuous anomalous Hall conductivity at the phase transition, in contrast to the very continuous holographic Weyl semimetal/trivial semimetal phase transition. Our work reveals the novel phase structure of strongly interacting Weyl semimetal.

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Yan Liu, Junkun Zhao. 2018-09-23. Weyl semimetal/insulator transition from holography. https://doi.org/10.1007/jhep12(2018)124

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