Endless Dirac nodal lines and high mobility in kagome semimetal Ni3In2Se2 single crystal

Kagome-lattice crystal is crucial in quantum materials research, exhibiting unique transport properties due to its rich band structure and the presence of nodal lines and rings. Here, we investigate the electronic transport properties and perform first-principles calculations for Ni_3In_2Se_2 kagome topological semimetal. First-principle calculations indicate six endless Dirac nodal lines and two nodal rings with a π-Berry phase in the Ni_3In_2Se_2 compound. The temperature-dependent resistivity is dominated by two scattering mechanisms: s-d interband scattering occurs below 50 K, while electron-phonon (e-p) scattering is observed above 50 K. The magnetoresistance (MR) curve aligns with the theory of extended Kohler's rule, suggesting multiple scattering origins and temperature-dependent carrier densities. A maximum MR of 120% at 2 K and 9 T, with a maximum estimated mobility of approximately 3000 cm^2V^-1s^-1 are observed. The Ni atom's hole-like d_x^2-y^2 and electron-like d_z^2 orbitals exhibit peaks and valleys, forming a local indirect-type band gap near the Fermi level (E_F). This configuration enhances the motion of electrons and holes, resulting in high mobility and relatively high magnetoresistance.