Robustness in ferromagnetic phase stability, half‐metallic behavior and transport properties of cobalt‐based full‐Heuslers compounds: A first principles approach

Abstract

AbstractHeusler alloys fill up the demanding gaps and becomes a point of prestige due to their interesting multi‐dimensional and remarkable applications in future technologies like spintronics and thermoelectrics. Self‐consistent ab‐initio calculations with highly precise spin‐polarized density functional theory associated with Boltzmann transport scheme have been perform to investigate the structural stability, mechanical, magneto‐electronic, thermo‐physical and thermoelectric transport properties of Co2VX (X = Sn, Sb) Heuslers. The equilibrium lattice parameters at the cost of structural optimizations are observed to agree with the available experimental data. The occurrence of perfect band occupation and interpretation of density of states through the modified version of Becke Johnson scheme delivers more precise and accurate results rather than GGA and GGA + U, possessing an indirect band gap of 1.12 eV and 1.34 eV in spin down channel of Co2VX (X = Sn, Sb) Heuslers respectively. Robustness of various elastic constants and its other associated mechanical constituents against external forces is checked to define the stability of these alloys. The transport parameters like Seebeck coefficient, electrical and thermal conductivity, power factor and zT have been put together to express their thermoelectric response. Conservative estimates of Seebeck coefficient and zT demonstrate its extending application stand in thermoelectric energy harvesting technologies. Furthermore complete and precise description of thermo‐physical behavior of the vital quantities like Debye temperature, thermal expansion, Grüneisen parameter and specific heat were examined to check its thermo‐dynamical stability against temperature and pressure variation.