Strain-induced effect in magnetic and thermoelectric properties of ferromagnetic half-metal TaPtSi: Material computations

Abstract

This study systematically investigates the impact of tensile and compressive strains on the elastic, electronic, magnetic, and transport properties of the half-Heusler compound TaPtSi, employing density functional theory (DFT) in conjunction with Boltzmann transport calculations. Initially, the cubic crystal structure of the TaPtSi alloy was optimized for various magnetic configurations to determine the most stable magnetic phase. The computed elastic constants confirmed the mechanical stability of TaPtSi under varying isotropic strain conditions. Additionally, the findings revealed that applying isotropic strain alters the electronic structure and energy bandgap of the TaPtSi half-Heusler alloy. The TaPtSi alloy exhibits positive integer total magnetic moment values under different applied strain conditions, indicating ferromagnetic properties. The transport properties, such as the Seebeck coefficient (S), electrical conductivity (σ), and thermal conductivity (κ), along with the figure of merit (ZT), are computed as functions of temperature ranging from 100K to 1000K under different strain conditions. The figure of merit (ZT) for TaPtSi is 0.13 in its unstrained state and reaches its peak value of 1 at 10 % tensile strain at 1000 K, highlighting the potential of TaPtSi half Heusler alloy as an efficient thermoelectric material for high-temperature applications under isotropic tensile strain. Overall, the results show that the material TaPtSi half-Heusler alloy can be used for both spintronic and thermoelectric application.