Pressure-driven Lifshitz transition in type-II Dirac semimetal NiTe2

Band engineering in layered transition metal dichalcogenides (TMDs) leads to a variety of emergent phenomena and has obtained considerable attention recently. Transition metal ditelluride NiTe2 has been discovered experimentally to be a type-II Dirac semimetal at ambient pressure, and was predicted to display superconductivity in the monolayer limit. Here we systematically investigate the structural and electronic properties of type-II Dirac semimetal NiTe2 under high pressure. Room-temperature synchrotron x-ray diffraction and Raman scattering measurements reveal the stability of the pristine hexagonal phase up to 52.2 GPa, whereas both the pressure coefficient and linewidth of Raman mode E-g exhibit anomalies at a critical pressure P-c similar to 16 GPa. Meantime, Hall resistivity measurement indicates that the hole-dominated behavior maintains up to 15.6 GPa and transforms into electron-dominated behavior at higher pressures. Our findings consistently demonstrate a pressure-induced Lifshitz transition in type-II Dirac semimetal NiTe2.