Planar Hall effect in the type-II Weyl semimetal Td−MoTe2

Abstract

Topological Weyl semimetals (WSMs), a new quantum state of matter, provide the realization of relativistic Weyl fermions in solid-state physics. The appearance of the Weyl nodes will demonstrate novel transport phenomena related to the chiral anomaly. Theoretical prediction hints that the giant planar Hall effect (PHE) can be induced by the chiral anomaly in the WSMs. In this work, we performed PHE measurements to probe chiral charge in type-II WSM ${T}_{d}\text{\ensuremath{-}}\mathrm{MoT}{\mathrm{e}}_{2}$. Robust transverse voltage can be acquired when the magnetic field and electric current is coplanar. Subsequently, the amplitude of intrinsic PHE increased sharply at $T=50\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ with the decreasing temperature. The increasing trend in the temperature dependence is attributed to coupling effect between the chiral charge and the electric one, which drives the system into intermediate-coupling states at higher field. Our work confirms that the PHE measurement is a practical transport tool to probe chiral charge pumping effect in the WSMs systems.