Atomic Layer and Interfacial Oxygen Defect Tailored Magnetic Anisotropy and Dzyaloshinskii–Moriya Interaction in Perovskite SrRuO₃/SrTiO₃ Heterostructures

It is significant to modulate the magnetic anisotropy energy (MAE) and Dzyaloshinskii–Moriya interaction (DMI) in perovskite-type transition metal oxides heterostructures toward the multifunctional spintronic devices. Here, the electronic structure and magnetic properties of SrRuO3(SRO)/SrTiO3 (STO) oxide heterostructures are investigated by first-principles calculations. As the SRO atomic layer increases from 3 to 9, the SRO/STO heterostructures show the perpendicular magnetic anisotropy (PMA), where PMA presents an oscillating characteristic due to the in-plane dx2–y2 and out-of-plane dxz + dxy + dz2 orbitals. The Ru magnetic moment reversal appears in SRO/STO heterostructure with 8 SRO atomic layers due to the hybridization of Ru d and O p orbitals. Moreover, the interfacial oxidation induces the transition of SRO from metallic to half-metallic, which also reverses the MAE and DMI signs of the deep RuO2 layer. These results indicate that atomic layer number and interfacial oxidation can effectively affect the electronic structure and magnetic properties of perovskite-type transition metal oxide heterostructures.