Magnetotransport properties of the type-II Weyl semimetal candidateTa3S2

Abstract

We have investigated the magnetoresistance (MR) and Hall resistivity properties of the single crystals of tantalum sulfide, ${\mathrm{Ta}}_{3}{\mathrm{S}}_{2}$, which was recently predicted to be a new type-II Weyl semimetal. Large MR (up to $\ensuremath{\sim}8000%$ at 2 K and 16 T), field-induced metal-insulator-like transition, and nonlinear Hall resistivity are observed at low temperatures. The large MR shows a strong dependence on the field orientation, leading to a giant anisotropic magnetoresistance effect. For the field applied along the $b$ axis $(B\ensuremath{\parallel}b)$, MR exhibits quadratic field dependence at low fields and tends towards saturation at high fields; while for $B\ensuremath{\parallel}a$, MR presents quadratic field dependence at low fields and becomes linear at high fields without any trend towards saturation. The analysis of the Hall resistivity data indicates the coexistence of a large number of electrons with low mobility and a small number of holes with high mobility. Shubnikov-de Haas oscillation analysis reveals three fundamental frequencies originated from the three-dimensional Fermi surface pockets. We find that the semiclassical multiband model is sufficient to account for the experimentally observed MR in ${\mathrm{Ta}}_{3}{\mathrm{S}}_{2}$.