Topological Weyl Phase Driven Anomalous Transport in Half-Metallic Co2ScSb Heusler Alloy

For the effective interconversion of heat energy into electricity, the thermoelectric devices based upon anomalous Nernst phenomena in topological Weyl materials can be of tremendous use in the near future. The present study shows a computational investigation of the topological properties along with the Anomalous Hall Conductivity (AHC) and Anomalous Nernst Conductivity (ANC) in the half-metallic ferromagnetic Co2ScSb Heusler alloy in the L21 structure as investigated using first-principles approach. A spin-orbit energy gap is opened up with the inclusion of SOC near the Fermi level, suggesting a topological nature of this material. Using the Green function approach, we obtained the Weyl semi-metallic characteristics in this material, which is confirmed by 10 pairs of Weyl nodes of opposite chirality, followed by WCC and a topological surface state. In addition, a nonzero large Berry curvature (Ωz (Å2)) along the (001) plane leads to a high AHC values of 271.05 Scm-1 at 0K. At room temperature, the value of ANC is about 1.9 Am-1K-1, which makes the Co2ScSb Heusler alloy a potential candidate for thermoelectric device applications. These large values of AHC and ANC are the consequence of the presence of Weyl nodes along the z=0 plane.