Atomistic structure and magnetic properties of the L10-MnAl|B2-CoAl heterojunction: A first-principles study

In this study, we have performed computational simulations, including spin-orbit coupling, to describe the atomistic structure of the L1 0 -MnAl|B2-CoAl heterostructure, a strong candidate for fabricating perpendicular magnetic tunnel junctions. We studied the thermodynamic stability and magnetic properties of several L1 0 -MnAl|B2-CoAl heterojunction models. At the interface layers, the most stable atomic arrangements form Mn Al layers from L1 0 -MnAl and B2-CoAl and Al Co layers from L1 0 -MnAl and B2-CoAl. These interface arrangements were compared to experimental HR-TEM images. Our analysis revealed that the interface is formed by Mn Al layers from L1 0 -MnAl and B2-CoAl, respectively. Also, we demonstrated that L1 0 -MnAl grows in the [001] and [110] directions. In addition, we find that the heterojunction has a perpendicular magnetic anisotropy (PMA) effect. Although B2-CoAl experiences a slight proximity-induced magnetization. As confirmed by a spin-density analysis, the ferromagnetic nature of L1 0 -MnAl dominates the interface magnetic behavior. • The stable interface configurations involve Mn Al pairs, which aligns with the HR-TEM experimental observations. • We confirm that L10-MnAl grows along the [001] and [110] crystallographic directions. • Heterostructure exhibits PMA as experimentally proven previously, highlighting its potential in applications for STT-MRAM devices. • DFT calculations validate the experimental findings.