Coexistence of Dirac and Weyl points in non-centrosymmetric semimetal NbIrTe4

Abstract

Using angle-resolved photoemission spectroscopy and density functional theory calculations methods, we investigate the electronic structures and topological properties of ternary tellurides NbIrTe4, a candidate for type-II Weyl semimetal. We demonstrate the presence of several Fermi arcs connecting their corresponding Weyl points on both termination surfaces of the topological material. Our analysis reveals the existence of Dirac points, in addition to Weyl points, giving both theoretical and experimental evidences of the coexistence of Dirac and Weyl points in a single material. These findings not only confirm NbIrTe4 as a unique topological semimetal but also open avenues for exploring novel electronic devices based on its coexisting Dirac and Weyl fermions.