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arXiv · 1708.07002

Hidden type-II Weyl points in the Weyl semimetal NbP

Shu-Chun Wu·Yan Sun·Claudia Felser·Binghai Yan
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Abstract

As one of Weyl semimetals discovered recently, NbP exhibits two groups of Weyl points with one group lying inside the $k_z=0$ plane and the other group staying away from this plane. All Weyl points have been assumed to be type-I, for which the Fermi surface shrinks into a point as the Fermi energy crosses the Weyl point. In this work, we have revealed that the second group of Weyl points are actually type-II, which are found to be touching points between the electron and hole pockets in the Fermi surface. Corresponding Weyl cones are strongly tilted along a line approximately $17^\circ$ off the $k_z$ axis in the $k_x - k_z$ (or $k_y - k_z$) plane, violating the Lorentz symmetry but still giving rise to Fermi arcs on the surface. Therefore, NbP exhibits both type-I ($k_z=0$ plane) and type-II ($k_z \neq 0$ plane) Weyl points.

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Shu-Chun Wu, Yan Sun, Claudia Felser, Binghai Yan. 2017-08-23. Hidden type-II Weyl points in the Weyl semimetal NbP. https://doi.org/10.1103/physrevb.96.165113

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