Using spin-and angle-resolved photoemission spectroscopy (spin-ARPES) together with calculations, we demonstrate the existence of a type-II Dirac semimetal state in NiTe . We show that, unlike PtTe , PtSe , and PdTe , the Dirac node in NiTe is located in close vicinity of the Fermi energy. Additionally, NiTe also hosts a pair of band inversions below the Fermi level along the high-symmetry direction, with one of them leading to a Dirac cone in the surface states. The bulk Dirac nodes and the ladder of band inversions in NiTe support unique topological surface states with chiral spin texture over a wide range of energies. Our work paves the way for the exploitation of the low-energy type-II Dirac fermions in NiTe in the fields of spintronics, THz plasmonics and ultrafast optoelectronics.
12 Aug 2019
arXiv preprint arXiv:1908.04099