Strain-modulated electronic and magnetic properties of Co2TMAl

Abstract

Discovery of magnetism in full-Heusler compounds opens up new opportunities due to their potential applications in spintronics. Here, we investigated the electronic and magnetic properties of full-Heusler Co2TMAl (TM = Ti, V, Cr, Mn, and Fe) compounds via strain engineering using density functional theory. It is found that biaxial strains along the ab-plane substantially affects the bond lengths, which further tune the magnetic moment and spin polarization (SP). The reorientation of the hybridization between TM and Co orbitals results in the variation of charge confinement that optimized physical properties. The most striking feature of the present study is the unusual response of Co2CrAl and Co2MnAl as a function of strain. For Co2CrAl, the robust half-metallicity is achieved under the biaxial compressive strains ranging from −1% to −5%, while tensile strain shows a negative impact. In the case of Co2MnAl, a substantial enhancement (decrease) in the SP magnitude is evident for compressive (tensile) strain. Hence, we affirm that strain can be an efficient way to tune the physical properties of Heusler compounds.