Quantum Effects of Impurities and Lattice Defects in Topological Semimetals

Abstract

Topological semimetals are a class of novel three-dimensional (3D) electronic phases that feature topologically protected conical band-touchings at the Fermi level. These band-touching points are monopoles of Berry curvature in momentum space and effectively realize (3+1)-dimensional Weyl fermions as emergent quasiparticles. Such features are robust to perturbations but not completely insensitive to them. In this thesis, we explore the yet fertile ground of disordered Weyl semimetals (WSMs), most notably by analysing the effects of on-site random fields, random smooth potential regions, point-like scalar impurities, and lattice point-defects in their electronic structure and electrodynamic properties.