Role of Coulomb Interactions in Weyl Semimetals: Renormalisation and Symmetry Breaking

Abstract

The discovery of graphene has drawn a lot of attention to a new phase of condensed matter systems, Dirac/Weyl semimetals. In these materials, electrons have a linear dispersion relation, making them a solid-state analogue of relativistic massless particles. Dirac/Weyl materials in three dimensions are found to be more stable than their 2D counterparts, e.g. graphene. In this research I focus on the role of Coulomb interactions between electrons within these systems. Using renormalisation group and mean filed theory approaches we investigate how the interaction influences the system parameters’ flow and breaks the symmetry spontaneously to create a mass gap.