Angle-dependent magnetotransport and quantum interference effect in type-II topological Dirac semimetal PtSe2

Abstract

We report the angle-dependent magnetoresistances (MRs) of platinum diselenide (PtSe2) in the Dirac semimetal phase. The negative longitudinal MR observed in parallel fields persists up to ∼50 K, which is quantitatively consistent with the chiral anomaly of Dirac fermions. When the field is perpendicular to the current, a low-field transition from positive to negative transverse MR is observed between 2 and ∼20 K, which is closely related to the quantum interference between time-reversed scattering paths, as well as the spin–orbit coupling strength. Our results reveal that the small-energy-transfer electron–electron scattering dominates the dephasing process in our PtSe2 films, providing experimental evidence for quantum interference transport in type-II Dirac fermion systems.