Symmetrical interfacial reconstruction and magnetism in La0.7Ca0.3MnO3/YBa2Cu3

et al.We have analyzed the interface structure and composition of La 0.7Ca0.3MnO3/YBa2Cu 3O7/La0.7Ca0.3MnO3 trilayers by combined polarized neutron reflectometry, aberration-corrected microscopy, and atomic column resolution electron-energy-loss spectroscopy and x-ray absorption with polarization analysis. We find the same stacking sequence at both top and bottom cuprate interfaces. X-ray magnetic circular dichroism experiments show that both cuprate interfaces are magnetic with a magnetic moment induced in Cu atoms as expected from symmetric Mn-O-Cu superexchange paths. These results supply a solid footing for the applicability of recent theories explaining the interplay between magnetism and superconductivity in this system in terms of the induced Cu spin polarization at both interfaces. © 2011 American Physical Society.Work at UCM was supported by Spanish MICINN Grant No. MAT 2008 06517, Consolider Ingenio CSD2009-00013 (IMAGINE), CAM S2009-MAT 1756 (PHAMA), and the European Research Council Starting InvestigatorAward, Grant No. 239739 STEMOX. Argonne National Laboratory’s work was supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357. This work has benefited from the use of the Lujan Neutron Scattering Center at LANSCE, which is funded by the Department of Energy’s Office of Basic Energy Sciences. Los Alamos National Laboratory is operated by Los Alamos National Security LLC under DOE through Contract No. DE-AC52-06NA25396. Work at ORNL (M.V. and S.J.P.) was supported by the Office of Science, Materials Sciences and Engineering Division of the U.S. Department of Energy.Peer Reviewe