Exploring the thermomagnetic behavior of Co2TiZ (Z=Al, Si, Ga, Ge, and Sn) alloys: a computational study

Abstract

A comprehensive computational exploration of the structural and thermomagnetic properties of Co2TiZ (Z = Al, Si, Ga, Ge, and Sn) Heusler alloys are conducted utilizing both density functional theory (DFT) and Monte Carlo simulations (MC). Our calculations revealed that the XA prototype consistently exhibited larger lattice parameters than the L21 structure. Furthermore, the investigation of exchange parameters uncovered distinct differences between the L21 and XA prototypes. The L21 structures consistently exhibited stronger Co-Co interactions, while the XA prototypes showcased more pronounced Co-Ti interactions. The calculated Curie temperatures (Tc) varied between the L21 and XA prototypes, highlighting the significance of atomic arrangement. The calculated critical temperature Tc of Co2TiAl exhibited variation depending on the structural prototype, and it is determined to be equal to 131K for the L21 prototype, while in the XA structure, it increases significantly to 248K. The higher Tc indicates improved thermal stability, expanding the material’s operational range and making it suitable for applications that require magnetic functionality at higher temperatures.