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تسجيل مستخدم جديدMagnetotransport properties of the type II Weyl semimetal candidate Ta3S2
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We have investigated the magnetoresistance (MR) and Hall resistivity properties of the single crystals of tantalum sulfide, Ta3S2, which was recently predicted to be a new type II Weyl semimetal. Large MR (up to ~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 (AMR) effect. For the field applied along the b-axis (B//b), MR exhibits quadratic field dependence at low fields and tends towards saturation at high fields; while for B//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 (SdH) oscillation analysis reveals three fundamental frequencies originated from the three-dimensional (3D) Fermi surface (FS) pockets. We find that the semi-classical multiband model is sufficient to account for the experimentally observed MR in Ta3S2.
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