Dissolution of topological Fermi arcs in a dirty Weyl semimetal

TL;DR

This paper numerically investigates how increasing disorder in Weyl semimetals causes Fermi arcs to gradually lose their sharpness and eventually dissolve into the bulk metallic phase at the quantum phase transition.

Contribution

It demonstrates the disorder-induced dissolution of Fermi arcs and characterizes the topological quantum phase transition in Weyl semimetals.

Findings

Fermi arcs gradually lose sharpness with increasing disorder

Fermi arcs completely dissolve at the Weyl metal transition

Bulk-boundary correspondence can be observed in ARPES and STM measurements

Abstract

Weyl semimetals (WSMs) have recently attracted a great deal of attention as they provide condensed matter realization of chiral anomaly, feature topologically protected Fermi arc surface states and sustain sharp chiral Weyl quasiparticles up to a critical disorder at which a continuous quantum phase transition (QPT) drives the system into a metallic phase. We here numerically demonstrate that with increasing strength of disorder the Fermi arc gradually looses its sharpness, and close to the WSM-metal QPT it completely dissolves into the metallic bath of the bulk. Predicted topological nature of the WSM-metal QPT and the resulting bulk-boundary correspondence across this transition can directly be observed in angle-resolved-photo-emmision-spectroscopy (ARPES) and Fourier transformed scanning-tunneling-microscopy (STM) measurements by following the continuous deformation of the Fermi arcs with increasing disorder in recently discovered Weyl materials.