Impact of terbium (Tb) on ferromagnetism and thermoelectric behaviour of spinels MgTb2(S/Se)4 for spintronic.

Density of states and band structures reveals 100% spin polarization and half metallic ferromagnetism. [Display omitted] • The Half metallic ferromagnetism, and spintronic applications. • Magnesium ion battertties and energy storage. • The ferromagnetism due to electron spin as an alternative of magnetic ion clustering. • Above room temperarue Curie temperature and 100% spin polarization. • Ultralow low thermal conductivity and Large value of electrical conductivity. The ferromagnetism due to rare earth elements-based spinel chalcogenides has become emerging aspirant for spintronic devices. Therefore, theoretically computed electronic properties of MgTb 2 (S/Se) 4 spinels are analyzed to comprehend the structural, magnetic, and thermoelectric characteristics. Thermodynamic stability is elucidated using the computed enthalpy of formation (ΔH), phonons dispersion band structures. Using structural optimizations, difference in the energy states has revealed the ferromagnetic (FM) state stability. The computed band structures (BS) and density of states (DOS) both depict a half-metallic ferromagnetic state exhibiting a net spin polarization at the Fermi energy level. The underlying ferromagnetic state has been suggested due to carrier mediated indirect RKKY exchange mechanism. The thermoelectric properties are calculated to evaluate their potential for wasted-heat to useful-electricity conversion applications. The small thermal conductivity, and high-power factor exhibited by MgTb 2 S 4 at room temperature suggest it significant for applications in thermoelectric generators. [ABSTRACT FROM AUTHOR]