Magnetoresistance and Kondo Effect in Nodal-Line Semimetal VAs_2

We performed calculations of the electronic band structure and the Fermi surface, measured the longitudinal resistivity \rho_xx(T,H), Hall resistivity \rho_xy(T,H), and magnetic susceptibility as a function of temperature at various magnetic fields for VAs_2 with a monoclinic crystal structure. The band structure calculations show that VAs_2 is a nodal-line semimetal when spin-orbit coupling is ignored. The emergence of a minimum at around 11 K in \rho_xx(T) measured at H = 0 demonstrates that some additional magnetic impurities (V^4+, S = 1/2) exist in VAs_2 single crystals, inducing Kondo scattering, evidenced by both the fitting of \rho_xx(T) data and the susceptibility measurements. It is found that a large positive magnetoresistance (MR) reaching 649% at 10 K and 9 T, its nearly quadratic field dependence, and a field-induced up-turn behavior of \rho_xx(T) also emerge in VAs_2, although MR is not so large due to the existence of additional scattering compared with other topological nontrivial/trivial semimetals. The observed properties are attributed to a perfect charge-carrier compensation, which is evidenced by both the calculations relying on the Fermi surface and the Hall resistivity measurements. These results indicate that the compounds containing V (3d^3 4s^2) element can be as a platform for studying the influence of magnetic impurities to the topological properties.