Comprehensive computational study of phase stability, half metallicity, elastic and thermal properties of Fe based quaternary Heusler alloys for spintronics applications

Abstract

Physical characteristics of quaternary Heusler alloys (QHAs) FeNbYZ (Z = Al, Ga, In, Sn) are determined using full potential linearized augmented plane wave (FP-LAPW) method within the framework of density functional theory (DFT) by implying generalized gradient approximation (GGA) and Perdew-Burke-Ernzerhof (PBE) exchange potential. First of all, structural stability is investigated to find the most optimized structure. The geometry optimization results indicated that the third type has the most stable structure among other two types along with ferromagnetic (FM) phase stability. The calculated band structures (BS) and density of states (DOS) indicated that these QHAs are half metals (HMs) having bang gap at only spin down channel. The computed magnetic moments (MMs) of FeNbYAl, FeNbYGa, FeNbYSn and FeNbYIn are compared with the MMs that obtained from Slater Pauling rule (SPR). These materials being totally spin polarization (SP) (i.e., 100%) had high Curie temperature (Tc) and high MM showing them half metallic nature and good to be used in useful applications. The mechanical stability is determined by computing elastic constants, bulk modulus, Young modulus, hardness, and Poisson ratio. The findings of mechanical attributes deduce that all investigated QHAs are ductile and had Pugh’s ratio > 1.75 making these materials mechanically stable. Furthermore, the calculations of thermoelectric properties have shown that these alloys could be utilized as thermoelectric in addition to spintronics. © 2023, Indian Association for the Cultivation of Science.