Large magnetoresistance in the type-II Weyl semimetal semimetal WP[subscript 2]

Abstract

We report a magnetotransport study on type-II Weyl semimetal WP[subscript 2] single crystals. Magnetoresistance exhibits a nonsaturating H[superscript n] field dependence (14 300% at 2 K and 9 T), whereas systematic violation of Kohler's rule was observed. Quantum oscillations reveal a complex multiband electronic structure. The cyclotron effective mass close to the mass of free electron m[subscript e] was observed in quantum oscillations along the b axis, while a reduced effective mass of about 0.5m[subscript e] was observed in a-axis quantum oscillations, suggesting Fermi surface anisotropy. The temperature dependence of the resistivity shows a large upturn that cannot be explained by the multiband magnetoresistance of conventional metals. Even though the crystal structure of WP[subscript 2] is not layered as in transition-metal dichalcogenides, quantum oscillations suggest partial two-dimensional character.