Investigations on Full-Heusler Alloys MnTaAl and MnWAl for Spintronic and Thermoelectric Applications

Half-metallic materials are widely used as spintronic devices such as electrodes, magnetic tunneling junction, and giant magnetoresistance. In this work, we have systematically investigated the structural stability, Gilbert damping, electronic structure, and magnetism together with exchange interactions and Curie temperatures for MnTaAl and MnWAl alloys. Initially, we estimate their structural stability and offer possible phase synthesis. Subsequently, the Gilbert damping parameters calculated by the linear response theory are used to assess their response speed as spintronic materials. Furthermore, the MnTaAl and MnWAl are predicted to be half-metallic and nearly half-metallic ferrimagnets and their total magnetic moments obey the  = -18 rule. Accordingly, their Curie temperatures for MnTaAl and MnWAl are also evaluated by the mean-field approximation. Finally, their thermodynamic parameters within 0∼600 K and thermoelectric properties within 200900 K are discussed. Overall, our research for MnTaAl and MnWAl alloys might provide some valuable clues for their application in spintronic devices.