Giant anisotropic magnetoresistance and planar Hall effect in the Dirac semimetal Cd3As2

TL;DR

This paper reports the discovery of giant anisotropic magnetoresistance and planar Hall effect in the Dirac semimetal Cd3As2, revealing new transport phenomena linked to Berry curvature in nonmagnetic topological materials.

Contribution

The study provides the first experimental observation of giant anisotropic magnetoresistance and planar Hall effect in a nonmagnetic Dirac semimetal, highlighting the role of Berry curvature.

Findings

Anisotropic magnetoresistance up to -68% at 2 K and 10 T.

Observation of the planar Hall effect in Cd3As2.

Attribution of effects to Berry curvature-induced current.

Abstract

Anisotropic magnetoresistance is the change tendency of resistance of a material on the mutual orientation of the electric current and the external magnetic field. Here, we report experimental observations in the Dirac semimetal Cd3As2 of giant anisotropic magnetoresistance and its transverse version, called the planar Hall effect. The relative anisotropic magnetoresistance is negative and up to -68% at 2 K and 10 T. The high anisotropy and the minus sign in this isotropic and nonmagnetic material are attributed to a field-dependent current along the magnetic field, which may be induced by the Berry curvature of the band structure. This observation not only reveals unusual physical phenomena in Weyl and Dirac semimetals, but also finds additional transport signatures of Weyl and Dirac fermions other than negative magnetoresistance.