A THEORETICAL STUDY OF ANOMALOUS NERNST CONDUCTIVITY WITH A WEYL-SEMIMETAL PHASE IN Co2YSb HEUSLER ALLOY

Abstract

Magnetic Weyl semimetals (WSM) are a distinctive category of topological quantum materials that exhibit pairs of non-degenerate band-crossing points, called as Weyl nodes. A defining feature of WSM is the presence of symmetry-protected Fermi arcs that connect Weyl nodes of opposite chirality. We conduct a systematic investigation of the electronic, magnetic, Topological, and anomalous transport properties of Co₂YSb Full Heusler alloy through the Density Functional Theory. The spin-polarised density of states reveals the half-metallicity and ferromagnetic nature of the material. The electronic structure indicates the presence of Topological Nodal lines, which are gapped out with the inclusion of Spin-Orbital coupling (SOC). To probe the Topological characteristics of Co₂YSb, we conduct a Wannier-function-based tight binding calculation with the effect of SOC and obtain the 12 pairs of Weyl nodes of opposite chirality. The presence of symmetry protected Topological Fermi arc and surface state confirms the Weyl semi-metallic nature of this material. Furthermore, the anomalous Hall and Anomalous Nernst conductivity are computed along the (001) plane. Therefore, our work highlights the interplay between topology and anomalous transport phenomena in the systematic investigation of the electronic, magnetic, Topological, and anomalous transport properties of Co₂YSb magnetic Heusler alloys, with their wide applications in spintronics and thermoelectric devices.