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arXiv · 1802.02632

Anisotropic fixed points in Dirac and Weyl semimetals

Oscar Pozo·Yago Ferreiros·María A. H. Vozmediano
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Abstract

The effective low energy description of interacting Dirac and Weyl semimetals is that of massless quantum electrodynamics with several Lorentz breaking material parameters. We perform a renormalization group analysis of Coulomb interaction in anisotropic Dirac and Weyl semimetals and show that the anisotropy persists in the material systems at the infrared fixed point. In addition, a tilt of the fermion cones breaking inversion symmetry induces a magnetoelectric term in the electrodynamics of the material whose magnitude runs to match that of the electronic tilt at the fixed point.

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Oscar Pozo, Yago Ferreiros, María A. H. Vozmediano. 2018-09-25. Anisotropic fixed points in Dirac and Weyl semimetals. https://doi.org/10.1103/physrevb.98.115122

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