UC Davis

Epitaxial La0.7Sr0.3MnO3(LSMO)/La0.7Sr0.3FeO3 (LSFO) superlattices serve as model systems to explore the magnetic structure and exchange coupling at (111)-oriented perovskite oxide interfaces. The (111) orientation possesses a buckled honeycomb structure resembling that of graphene with the stacking of highly polar layers. Furthermore, the bulk LSFO magnetic structure suggests that an ideal (111) interface should have fully uncompensated antiferromagnetic (AF) moments leading to exchange bias interactions. Detailed soft x-ray magnetic spectroscopy and microscopy reveal that interfacial effects and ultrathin superlattice sublayers can stabilize orientations of the LSFO AF spin axis, which differ from that of LSFO films and LSMO/LSFO bilayers. A portion of the AF moments can be reoriented to an arbitrary direction by a moderate external magnetic field through spin-flop coupling with the ferromagnetic LSMO sublayers that have low magnetocrystalline anisotropy in the (111) plane.