Tuning magnetic anisotropy by interfacial engineering in SrFeO _2.5 /La _2/3 Ba _1/3 MnO ₃ /SrFeO _2.5 trilayers

Abstract

Abstract Exploring emergent phenomena in complex oxide heterostructures by interfacial engineering is the frontier of the oxide electronics. The heterointerface formed by oxides with different structures is particularly interesting since symmetry mismatch may produce considerable interface reconstruction and unexpected emergent phenomena. Here, we demonstrate the abnormal magnetic anisotropy in SrFeO 2.5 /La 2/3 Ba 1/3 MnO 3 /SrFeO 2.5 trilayers that are consisted of the perovskite/brownmillerite heterostructures. The compressively strained La 2 / 3 Ba 1 / 3 MnO 3 layer sandwiched between the two SrFeO 2.5 layers exhibits in-plane magnetic anisotropy, while the La 2 / 3 Ba 1 / 3 MnO 3 bare film with the same strain state shows perpendicular magnetic anisotropy at low temperature. The high-resolution scanning transmission electron microscope and x-ray absorption spectroscopy analysis reveal the off-center displacement of the Mn ions at interfaces. This would cause a strong orbital reconstruction of Mn ions at the interface and thus the in-plane magnetic anisotropy. This work shows the great potential to explore novel phenomena in artificially designed multilayers by interfacial engineering.