Magnetotransport evidence for topological phase transition in a Dirac semimetal

Abstract

Dirac semimetals transform into Weyl semimetals by breaking the time reversal symmetry, resulting in interesting physical properties, such as the chiral anomaly induced negative magnetoresistance and the Weyl orbit related quantum transport. Here, we report the disappearance of the Weyl semimetal phase in Dirac semimetal Cd3As2 nanoplates with a (112) surface plane when applying a perpendicular high magnetic field. The Landau fan extracted from the notable quantum oscillations shows the nontrivial Berry phase πfor B < 9.4 T and its disappearance at around 1 / B ∼ 0.1 T - 1. Our observations indicate the topological phase transition from nontrivial states to gap-opening states induced by the C 4 rotational symmetry breaking under a high magnetic field.