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arXiv · 1511.07440

MoTe2: A Type-II Weyl Topological Metal

Zhijun Wang·Dominik Gresch·Alexey A. Soluyanov·Weiwei Xie·S. Kushwaha·Xi Dai·Matthias Troyer·Robert J. Cava·B. Andrei Bernevig
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Abstract

Based on the ab initio calculations, we show that MoTe2, in its low-temperature orthorhombic structure characterized by an X-ray diffraction study at 100 K, realizes 4 type-II Weyl points between the N-th and N+1-th bands, where N is the total number of valence electrons per unit cell. Other WPs and nodal lines between different other bands also appear close to the Fermi level due to a complex topological band structure. We predict a series of strain-driven topological phase transitions in this compound, opening a wide range of possible experimental realizations of different topological semimetal phases. Crucially, with no strain, the number of observable surface Fermi arcs in this material is 2 - the smallest number of arcs consistent with time-reversal symmetry.

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Zhijun Wang, Dominik Gresch, Alexey A. Soluyanov, Weiwei Xie, S. Kushwaha, Xi Dai, Matthias Troyer, Robert J. Cava, B. Andrei Bernevig. 2016-07-28. MoTe2: A Type-II Weyl Topological Metal. https://doi.org/10.1103/physrevlett.117.056805

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