The effect of insertion layer on the perpendicular magnetic anisotropy and its electric-field-induced change at Fe/MgO interface: a first-principles investigation

The development of ultralow power and high density nonvolatile magnetic random access memory stimulates the search for promising materials in magnetic tunnel junction with large voltage-controlled magnetic anisotropy (VCMA) efficiency. In this work, we investigate the 4d and 5d transition metal interlayer effect on perpendicular magnetic anisotropy (PMA) and VCMA at Fe/MgO interface by using first-principles calculations. Large PMA more than 11 mJ m⁻² is found at Fe/MgO interface with Pt insertion layer and the mechanism for PMA is clarified based on the second order perturbation theory. Furthermore, we find that the magnitude and the sign of VCMA efficiency are varied by introducing different insertions at Fe/MgO interface. The Re and Os interlayers lead to a sizable increase in both of the PMA and the VCMA coefficient. Our findings may further emphasize the essential importance of the interface structure on PMA and VCMA and may offer new material platforms for low-power consumption spintronic devices. (paper)