In-plane magnetoresistance of HfTe₅ changes sign with temperature
Rotating the field within the crystal plane revealed temperature-dependent anisotropic magnetoresistance and a planar Hall signal.
The authors compared in-plane transport at different temperatures in nonmagnetic HfTe₅ flakes. Below the temperature of the resistivity anomaly, the anisotropic magnetoresistance turned negative. The negative longitudinal response was strongest when the in-plane field was perpendicular to the current.
The team proposed reduced spin scattering through field-driven coupling of the top and bottom surface states as one explanation. Peng Wang and Tao Hou shared first authorship; Hualing Zeng, Liyuan Zhang and Zhenhua Qiao were corresponding authors. The December 2020 online publication appeared in the January 2021 issue.