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arXiv · 1712.10200

Non-stoichiometry effects on the extreme magnetoresistance in Weyl semimetal WTe2

J. X. Gong·J. Yang·M. Ge·Y. J. Wang·D. D. Liang·L. Luo·X. Yan·W. L. Zhen·S. R. Weng·L. Pi·C. J. Zhang·W. K. Zhu
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Abstract

Non-stoichiometry effect on the extreme magnetoresistance is systematically investigated for the Weyl semimetal WTe2. Magnetoresistance and Hall resistivity are measured for the as-grown samples with a slight difference in Te vacancies and the annealed samples with increased Te vacancies. The fittings to a two-carrier model show that the magnetoresistance is strongly dependent on the residual resistivity ratio (i.e., the degree of non-stoichiometry), which is eventually understood in terms of electron doping which not only breaks the balance between electron-type and hole-type carrier densities but also reduces the average carrier mobility. Thus, compensation effect and ultrahigh mobility are probably the main driving force of the extreme magnetoresistance in WTe2.

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J. X. Gong, J. Yang, M. Ge, Y. J. Wang, D. D. Liang, L. Luo, X. Yan, W. L. Zhen, S. R. Weng, L. Pi, C. J. Zhang, W. K. Zhu. 2017-12-29. Non-stoichiometry effects on the extreme magnetoresistance in Weyl semimetal WTe2. https://doi.org/10.1088/0256-307x%2F35%2F9%2F097101

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