Atomic-scale visualization of quasiparticle interference on a type-II Weyl semimetal surface

TL;DR

This study combines theoretical simulations and atomic-scale experiments to visualize and analyze quasiparticle interference patterns on a type-II Weyl semimetal surface, revealing topological surface states and their scattering behaviors.

Contribution

It is the first to experimentally visualize quasiparticle interference on a type-II Weyl semimetal surface and connect surface states with bulk topology.

Findings

Identification of topological Fermi arc states

Visualization of surface electron scattering behavior

Experimental signature of bulk-surface state interconnectivity

Abstract

We combine quasiparticle interference simulation (theory) and atomic resolution scanning tunneling spectro-microscopy (experiment) to visualize the interference patterns on a type-II Weyl semimetal Mo$_{x}$W$_{1-x}$Te$_2$ for the first time. Our simulation based on first-principles band topology theoretically reveals the surface electron scattering behavior. We identify the topological Fermi arc states and reveal the scattering properties of the surface states in Mo$_{0.66}$W$_{0.34}$Te$_2$. In addition, our result reveals an experimental signature of the topology via the interconnectivity of bulk and surface states, which is essential for understanding the unusual nature of this material.