Magneto-resistance study on single crystals of NbAs_2 semimetal

摘要

Here we report the single crystal growth, characterization, magneto-transport and magnetization studies of NbAs_2 semimetal. The zero field resistivity vs temperature shows metallic behaviour with large residual resistivity ratio. Field measurements show an upturn in resistivity at low temperatures and subsequent saturation. The transverse magneto-resistance reveals a large unsaturated MR reaching 1.1 × 10~5 % at 2.5 K and a field of 14 T with Shubnikov de Haas oscillations. Kohler's rule analysis suggests same scattering mechanism operating across the temperature regime from 300 K down to 2.5 K except at very low MR region indicating the role of a critical field. The absence of negative magneto-resistance in the longitudinal measurement points out that NbAs_2 is not a conventional Weyl semimetal. The non-linear Hall resistance behavior evinces the presence of multiple carriers in the system. The de Haas van Alphen oscillations in the magnetization measurement display anisotropy with respect to the crystalline direction.