Strain control of magnetic phase transition and perpendicular magnetic anisotropy in Ta/FeRh/MgO(001) heterostructure

Employing first-principles calculations, we reveal tremendous strain effects on the magnetic order and magnetic anisotropy energy (MAE) of Ta-capped FeRh films on MgO(001). It is found that the tensile strain can lead to the magnetic phase transition from a ferromagnetic to an antiferromagnetic state at the FeRh/MgO and Ta/FeRh interfaces. Furthermore, we demonstrate that magnetization direction of Ta/FeRh/MgO(001) can reverse from perpendicular to in-plane orientation by tuning the strain, in contrast to the strain-independent perpendicular magnetization in FeRh/MgO(001). The underlying mechanism is discussed in connection with the strain-induced interfacial magnetic phase transition and changes in Fe 3d-Ta 5d hybridization at the interface. These findings open interesting prospects for exploiting stain manipulation of magnetization switching across the magnetic phase transition of FeRh layers for the next generation of antiferromagnetic memory devices.