First-principles study of CsVTe half-Heusler alloy aimed at spintronic and thermoelectric uses

This study investigates the structural, elastic, mechanical, electrical, magnetic, and thermoelectric properties of the half-Heusler CsVTe alloy using density functional theory (DFT). The GGA-PBE and GGA + U approximations are employed to accurately assess these characteristics. The results show that CsVTe is most stable in the ferromagnetic (FM) configuration, compared to the nonmagnetic (NM) and antiferromagnetic (AFM) phases. Density of states analysis reveals that CsVTe exhibits ferromagnetic half-metallic behavior in both GGA-PBE and GGA + U approximations, highlighting its potential for spintronic applications. A detailed investigation of the alloy's elastic and mechanical properties confirms its mechanical stability. Thermodynamic stability is further validated through the use of a ternary convex hull diagram. However, the presence of negative frequencies in the phonon dispersion curve suggests that HH-CsVTe may exist in a metastable phase. Additionally, the thermoelectric properties of HH-CsVTe were evaluated using both GGA-PBE and GGA + U methods. The results show a high ZT value close to 1 for the spin-down channel, indicating CsVTe's potential for thermoelectric applications.