Non-Abelian anomalies in multi-Weyl semimetals

Abstract

This article reveals the presence of non-Abelian anomaly, manifesting through the non-conservation of the isospin density, in Lorentz asymmetric Weyl materials, possessing nonlinear band dispersion. Pursuing effective field theoretic and lattice-based numerical approaches, the authors show that such an anomalous violation of isospin density is jointly governed by the topological invariant (monopole charge) and certain algebraic property of the SU(2) Lie group. Whereas only the former one determines the non-conservation of the Abelian charge. The authors further substantiate these predictions from strong coupling holographic duality.