Anisotropic planar Hall effect in the type-II topological Weyl semimetal WTe2

The giant planar Hall effect arising from a chiral anomaly, and that is related to the Berry curvature, has been predicted but never observed in nonmagnetic type-II Dirac/Weyl semimetals. Here, we report an observation of the anisotropic planar Hall effect in type-II Weyl semimetal WTe2. Interestingly, we observe a chiral-anomaly-induced sinusoidal angular-dependent planar Hall effect when the electric field is parallel to the tilting direction of Weyl cone, i.e., the b axis of WTe2. The planar Hall effect amplitude is linearly dependent on the magnetic fields and decreases gradually as the temperature increases across the topological phase transition temperature. Our observations clearly reveal the footprints on transport from the chiral anomaly feature in type-II Weyl semimetals.