Mirror protected Dirac fermions on a Weyl semimetal NbP surface

TL;DR

This study reveals mirror symmetry-protected Dirac cones on NbP Weyl semimetal surfaces using scanning tunneling spectroscopy, providing insights into their electronic structure and surface properties.

Contribution

It demonstrates the existence of mirror symmetry-protected Dirac fermions on NbP surfaces and characterizes their electronic properties with high-resolution spectroscopy and theoretical support.

Findings

Identification of mirror symmetry-protected Dirac cones on NbP surfaces

Resolution of quantum interference patterns of Dirac fermions

Comparison of these Dirac fermions with those in topological crystalline insulators

Abstract

The first Weyl semimetal was recently discovered in the NbP class of compounds. Although the topology of these novel materials has been identified, the surface properties are not yet fully understood. By means of scanning tunneling spectroscopy, we find that NbPs (001) surface hosts a pair of Dirac cones protected by mirror symmetry. Through our high resolution spectroscopic measurements, we resolve the quantum interference patterns arising from these novel Dirac fermions, and reveal their electronic structure, including the linear dispersions. Our data, in agreement with our theoretical calculations, uncover further interesting features of the Weyl semimetal NbPs already exotic surface. Moreover, we discuss the similarities and distinctions between the Dirac fermions here and those in topological crystalline insulators in terms of symmetry protection and topology.