HoBi: The Effect of Magnetism on Extreme Magnetoresistance*

Since the discovery of extreme magnetoresistance (XMR) in the topological semimetal WTe2, this phenomenon, featuring extremely high and non-saturating MR, has been found in many topological materials. In some cases, it is shown that XMR does not necessarily connect to topology and can be explained by electron-hole compensation unambiguously [1]. Although we have better understood the role of topology in XMR, the effect of magnetism on XMR remains elusive. Previous studies showed the power-law field dependence of XMR holds in both non-magnetic and magnetic XMR materials and is robust against magnetism. In this work [2], we focus on HoBi in the rare-earth monopnictide material family, which has an antiferromagnetic ground state with huge moments. We find an exact correspondence between the phase diagrams mapped by magnetization and transport measurements. Interestingly, we also find the XMR of HoBi is significantly affected by its magnetic order with ordering vector (1/6,1/6,1/6), in strong contrast to its family members like CeSb. The interplay between magnetism and transport makes HoBi a great platform to understand XMR in magnetic semimetals with trivial or non-trivial topology.
References:
[1] Physical Review B 96, 235128 (2017)
[2] Physical Review B 98, 045136 (2018)