Renormalization Group Approach to Stability of Interacting Type-II Weyl Fermions

Ze-Min Huang, Jianhui Zhou, Shun-Qing Shen

Published 2016-09-06Version 1

The type-II Weyl fermions are a generalization of conventional Weyl fermions, whose conic spectrum is tilted such that the Fermi surface becomes lines in two dimension, and surface in three dimension rather than discrete points. The renormalization group approach is employed to study the stability of two-dimensional type-II Weyl fermions against the Coulomb interaction. It is found that, because of the nontrivial Fermi surface, the logarithmic divergence of the Fermi velocity in conventional Weyl fermions is suppressed. The infrared stable fixed points indicate that the Fermi surface of type-II anisotropic Weyl fermions is stable against the Coulomb interaction. In addition, the finite photon mass partially originates from the chiral anomaly and leads to the screening effect. This work provides deep insight into the interplay between the geometry of Fermi surface and the Coulomb interaction.