Nodal vacancy bound states and resonances in three-dimensional Weyl semimetals

TL;DR

This paper investigates how atomic-sized vacancy defects in three-dimensional Weyl semimetals create bound states and resonances, significantly affecting their electronic structure and scattering properties.

Contribution

It reveals that vacancies induce nodal bound states with specific asymptotic behavior and demonstrates their impact on the density of states and electronic structure modifications.

Findings

Vacancies generate nodal bound states with $r^{-2}$ tails.

Increasing vacancy concentration broadens the nodal peak into satellite resonances.

Point defects cause significant elastic scattering, altering electronic properties.

Abstract

The electronic structure of a cubic $\mathcal{T}$-symmetric Weyl semimetal is analysed in the presence of atomic-sized vacancy defects. Isolated vacancies are shown to generate nodal bound states with $r^{{\scriptscriptstyle -2}}$ asymptotic tails, even when immersed in a weakly disordered environment. These states show up as a significantly enhanced nodal density of states which, as the concentration of defects is increased, reshapes into a nodal peak that is broadened by inter-vacancy hybridisation into a comb of satellite resonances at finite energies. Our results establish point defects as a crucial source of elastic scattering that leads to nontrivial modifications in the electronic structure of Weyl semimetals.