Interplay between spin polarization and superconductivity in an ex-situ bilayer La 0.67 Ca 0.33 MnO 3 — YBa 2 Cu 3 O 7-δ

An anomalous magnetism is observed in an ex-situ bilayer of high-temperature superconductor YBa 2 Cu 3 O 7-δ and colossal magnetoresistive material La 0.67 Ca 0.33 MnO 3 . The magnetism results in strong in-plane anisotropy of the resistance and surprising peak in the temperature dependence of resistance below superconducting transition associated with the interplay between superconductivity and establishment of the magnetic order. Magneto-optical-imaging reveals a stripy magnetic structure in the bilayer linked with unusual behavior of the resistance. The magnetization measurements demonstrate strong and irreversible magnetism, which is likely associated with reorientation of the magnetic moment of interface. The observed non-linear resistance could find practical use exploring further link between superconductivity and magnetism of the interface.