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arXiv · 1601.04618

Large magnetoresistance in LaBi: origin of field-induced resistivity upturn and plateau in compensated semimetals

Abstract

The discovery of non-magnetic extreme magnetoresistance (XMR) materials has induced great interests because the XMR phenomenon challenges our understanding of how a magnetic field can alter electron transport in semimetals. Among XMR materials, the LaSb shows XMR and field-induced exotic behaviors but it seems to lack the essentials for these properties. Here, we study the magnetotransport properties and electronic structure of LaBi, isostructural to LaSb. LaBi exhibits large MR as in LaSb, which can be ascribed to the nearly compensated electron and hole with rather high mobilities. More importantly, our analysis suggests that the XMR as well as field-induced resistivity upturn and plateau observed in LaSb and LaBi can be well explained by the two-band model with the compensation situation. We present the critical conditions leading to these field-induced properties. It will contribute to understanding the XMR phenomenon and explore novel XMR materials.

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Shanshan Sun, Qi Wang, Peng-Jie Guo, Kai Liu, Hechang Lei. 2016-08-06. Large magnetoresistance in LaBi: origin of field-induced resistivity upturn and plateau in compensated semimetals. https://doi.org/10.1088/1367-2630%2F18%2F8%2F082002

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