TRANSPORT-PROPERTIES OF YBA2CU3O7-DELTA FERROMAGNETIC INTERFACES

The transport properties of YBa2Cu3O7-delta/permalloy interfaces as a function of temperature and small magnetic fields are presented. High quality (001) and (100) oriented YBa2Cu3O7-delta (YBCO) thin films are prepared by the off-axis sputtering technique. Permalloy (Ni0.8Fe0.2) films are then deposited on top of the YBCO films, and patterned in order to obtain sub-millimeter contacts. The interface resistances in the normal and superconducting state of the YBCO are measured as a function of an applied magnetic field. The results are discussed in the framework of electron spin transport across the interface and spin diffusion in the bulk of the superconductor.