Abstract
•The structure of the theoretical prediction is exactly the same as the experiment.•Co2NbGa alloy is a half-metallic ferromagnet with 100% spin polarization.•Co2NbGa alloy is an anisotropic material with stable mechanical properties.•Curie temperature of Co2NbGa alloy is slightly higher than room temperature.
The phase structures, magnetic properties, electronic structures, and anisotropy of the full Heusler alloy Co2NbGa were studied using the first-principles method, and the results were compared with experiments. The L21-type cubic structure was the most stable, which was in good agreement with the experimental measurement. The Curie temperature obtained by the mean field theory was also very close to the experimental value. The electronic structures and magnetic properties showed that the Co2NbGa alloy was a half-metallic ferromagnet with 100% spin polarization at equilibrium, and the robustness of the half-metallic feature was preserved in lattice ranges of 5.79 to 6.42 Å. The Co2NbGa alloy was an anisotropic material with stable mechanical properties at L21-type cubic and XA-type tetragonal structures, and the influence of Hubbard U and vacancy defects on the physical nature was also studied and discussed. The 100% spin polarization, high Curie temperature, and stable equilibrium structure make Co2NbGa alloy a promising candidate in spintronics and magnetoelectronic.