Probing the Chiral Anomaly by Planar Hall Effect in Three-dimensional Dirac Semimetal Cd3As2 Nanoplates

TL;DR

This study demonstrates the observation of the planar Hall effect in Cd3As2 nanoplates, providing new transport evidence for the chiral anomaly in Dirac semimetals and revealing its temperature dependence.

Contribution

It is the first to report the planar Hall effect in Cd3As2 nanoplates, linking it to the chiral anomaly and expanding understanding of topological transport phenomena.

Findings

Observation of PHE in Cd3As2 nanoplates at room temperature

PHE and negative LMR are suppressed with increasing temperature

Both effects are linked to the chiral anomaly

Abstract

Searching for exotic transport properties in new topological state of matters is an active topic. One of the most fascinating achievements is the chiral anomaly in recently discovered Weyl semimetals (WSMs), which is manifested as a negative longitudinal magnetoresistance (LMR) in the presence of a magnetic field B parallel to an electric field E. Another predicted key effect closely related to the chiral anomaly is the planar Hall effect (PHE), which has not been identified in WSMs so far. Here we carried out the planar Hall measurements on Cd3As2 nanoplates, and found that, accompanied by the large negative LMR, a PHE with non-zero transverse voltage can be developed while tilting the in-plane magnetic field B away from the electric field E. Further experiments reveal that both the PHE and the negative LMR can be suppressed synchronously by increasing the temperature, but still visible at room temperature, indicating the same origin of these two effects. The observation of PHE in Cd3As2 nanoplates gives another transport evidence for the chiral anomaly and provides a deep insight into the chiral charge pumping in Weyl Fermions system.