A magneto-optical analysis was made of YBa2Cu3O7-δ/La1-xSrxMnO3 bilayers grown onto twinned LaAlO3 substrates. The twin boundaries in the LaAlO3 substrate induced splitting of the manganite magnetic domains with either in-plane or out-of-plane magnetization; depending upon the Sr doping level affecting the magnetic pattern. In the YBa2Cu3O7-δ film, the spontaneous vortex phase, as induced by the out-of-plane magnetic moments in the manganite films, was directly visualized. For vortices nucleated by an external magnetic field, differing vortex dynamics were distinguished due to the out-of-plane magnetic moments located either in correlated defects (twin boundaries) or in an homogeneous part of the heterostructure.

Quantitative Magneto-Optical Analysis of Twinned YBa2Cu3O7-δ/La1-xSrxMnO3 Bilayers. L.Gozzelino, F.Laviano, P.Przyslupski, A.Tsarou, A.Wisniewski, D.Botta, R.Gerbaldo, G.Ghigo: Superconductor Science and Technology, 2006, 19, S50-4