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arXiv · 1505.07968

Robust linear magnetoresistance in WTe2

Abstract

Unsaturated magnetoresistance (MR) has been reported in WTe2, and remains irrepressible up to very high field. Intense optimization of the crystalline quality causes a squarely-increasing MR, as interpreted by perfect compensation of opposite carriers. Herein we report our observation of linear MR (LMR) in WTe2 crystals, the onset of which is first identified by constructing the mobility spectra of the MR at low fields. The LMR further intensifies and predominates at fields higher than 20 Tesla while the parabolic MR gradually decays. The LMR remains unsaturated up to a high field of 60 Tesla and persists, even at a high pressure of 6.2 GPa. Assisted by density functional theory calculations and detailed mobility spectra, we find the LMR to be robust against the applications of high field, broken carrier balance, and mobility suppression. Angle-resolved photoemission spectroscopy reveals a unique quasilinear energy dispersion near the Fermi level. Our results suggest that the robust LMR is the low bound of the unsaturated MR in WTe2.

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Xing-Chen Pan, Yiming Pan, Juan Jiang, Huakun Zuo, Huimei Liu, Xuliang Chen, Zhongxia Wei, Shuai Zhang, Zhihe Wang, Xiangang Wan, Zhaorong Yang, Donglai Feng, Zhengcai Xia, Liang Li, Fengqi Song, Baigeng Wang, Yuheng Zhang, Guanghou Wang. 2015-05-29. Robust linear magnetoresistance in WTe2. https://doi.org/10.1007/s11467-016-0629-7

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