Journal Article

Extended Kohler’s Rule of Magnetoresistance

Han, Fei, Kwok, Wai-Kwong, Chung, Duck Young, Fotovat, Roxanna, Kanatzidis, Mercouri G., Thoutam, Laxman R., Pate, Samuel E., Welp, Ulrich, Xu, Jing, Wang, Yong-Lei, Zhang, Xufeng, Xiao, Zhi-Li, Wang, Ting-Ting, Zhou, Xiuquan, Li, Mingda

2021

Overview

A notable phenomenon in topological semimetals is the violation of Kohler’s rule, which dictates that the magnetoresistance MR obeys a scaling behavior ofMR=f(H/ρ0), whereMR=[ρ(H)−ρ0]/ρ0andHis the magnetic field, withρ(H)andρ0being the resistivity atHand zero field, respectively. Here, we report a violation originating from thermally induced change in the carrier density. We find that the magnetoresistance of the Weyl semimetal TaP follows an extended Kohler’s ruleMR=f[H/(nTρ0)], withnTdescribing the temperature dependence of the carrier density. We show thatnTis associated with the Fermi level and the dispersion relation of the semimetal, providing a new way to reveal information on the electronic band structure. We offer a fundamental understanding of the violation and validity of Kohler’s rule in terms of different temperature responses ofnT. We apply our extended Kohler’s rule toBaFe2(As1−xPx)2to settle a long-standing debate on the scaling behavior of the normal-state magnetoresistance of a superconductor, namely,MR∼tan2θH, whereθHis the Hall angle. We further validate the extended Kohler’s rule and demonstrate its generality in a semiconductor, InSb, where the temperature-dependent carrier density can be reliably determined both theoretically and experimentally.

• Publisher: American Physical Society
• Subject: Carrier density / Conductors / Electric conductors / Magnetic fields / Magnetoresistance / Magnetoresistivity / Metalloids / Phase transitions / Phosphides / Scaling laws / Superconductors / Tantalum / Temperature dependence / Topology