A comprehensive ARPES study on the type-II Dirac semimetal candidate Ir1−xPtxTe2
Juan Jiang,
Sangjae Lee,
Fucong Fei,
Fengqi Song,
Elio Vescovo,
Konstantine Kaznatcheev,
Frederick J. Walker,
Charles H. Ahn
Affiliations
Juan Jiang
Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA
Sangjae Lee
Department of Physics, Yale University, New Haven, Connecticut 06520, USA
Fucong Fei
National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and School of Physics, Nanjing University, 210093 Nanjing, China
Fengqi Song
National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and School of Physics, Nanjing University, 210093 Nanjing, China
Elio Vescovo
National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
Konstantine Kaznatcheev
National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
Frederick J. Walker
Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA
Charles H. Ahn
Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA
The transition metal dichalcogenide Ir1−xPtxTe2 displays both superconductivity and a topological band structure. Using angle-resolved photoemission spectroscopy, we obtain a comprehensive understanding of the three-dimensional electronic structure in the normal state of Ir1−xPtxTe2 for doping levels from x = 0.1 to 0.4, which spans the composition range of a superconducting state to a non-superconducting state. Many features of the electronic structure can be attributed to strong Te–Te interactions between the layers of the layered crystal structure and can be resolved by photon energy dependent measurements. We demonstrate that the type-II Dirac fermions can be successfully tuned via Pt doping, where the Dirac point lies close to the Fermi level for x = 0.1. The band evolution vs doping provides a clearer understanding of the relationship between the superconductivity and electronic structure. In addition, the β band in the superconducting samples locates the system close to a type-II van Hove singularity, where spin triplet paring symmetry has been predicted. Our results provide a comprehensive understanding of the band structure of Ir1−xPtxTe2, and we discuss the possibilities of the existence of topological superconductivity in this system.
