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arXiv · 1706.09830

Magnetotransport properties of MoP$_2$

Abstract

We report magnetotransport and de Haas-van Alphen (dHvA) effect studies on MoP$_2$ single crystals, predicted to be type-2 Weyl semimetal with four pairs of robust Weyl points located below the Fermi level and long Fermi arcs. The temperature dependence of resistivity shows a peak before saturation, which does not move with magnetic field. Large nonsaturating magnetoresistance (MR) was observed, and the field dependence of MR exhibits a crossover from semicalssical weak-field $B^2$ dependence to the high-field linear-field dependence, indicating the presence of Dirac linear energy dispersion. In addition, systematic violation of Kohler's rule was observed, consistent with multiband electronic transport. Strong spin-orbit coupling (SOC) splitting has an effect on dHvA measurements whereas the angular-dependent dHvA orbit frequencies agree well with the calculated Fermi surface. The cyclotron effective mass $\sim$ 1.6$m_e$ indicates the bands might be trivial, possibly since the Weyl points are located below the Fermi level. Interestingly, quasi-two dimensional(2D) band structure is observed even though the crystal structure of MoP$_2$ is not layered.

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Aifeng Wang, D. Graf, Yu Liu, C. Petrovic. 2017-06-29. Magnetotransport properties of MoP$_2$. https://doi.org/10.1103/physrevb.96.195107

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