We report a strong effect of interface-induced magnetization on the transport properties of magnetic tunnel junctions consisting of ferromagnetic manganite La0.7Ca0.3MnO3 and insulating cuprate PrBa2Cu3O7. Contrary to the typically observed steady increase of the tunnel magnetoresistance with decreasing temperature, this system exhibits a sudden anomalous decrease at low temperatures. Interesti...

We demonstrate a-axis YBa2Cu3O7−x/PrBa2Cu3O7−x/YBa2Cu3O7−x trilayers grown on (100) LaAlO3 substrates with improved interface smoothness. The are synthesized by ozone-assisted molecular-beam epitaxy. thickness of the PrBa2Cu3O7−x layer is held constant at 8 nm, and YBa2Cu3O7−x layers varied from 24 nm to 100 nm. X-ray diffraction measurements show all have >97% content. rms roughness thinnest t...

We present in this paper an overview of the work that has been performed on hightemperature superconductor superlattices, with a special emphasis on the superconducting properties of YBa2Cu3O7/PrBa2Cu3O7 multilayers. The critical temperature and superconductivity in ultra-thin films, the vortex dynamics, and the field-temperature vortex phase diagram in YBa2Cu3O7/PrBa2Cu3O7 multilayers are stud...

The (mostly) insulating behaviour of PrBa2Cu3O7−δ is still unexplained and even more interesting since the occasional appearance of superconductivity in this material. Since YBa2Cu3O7−δ is nominally iso-structural and always superconducting, we have measured the electron momentum density in these materials. We find that they differ in a striking way whereas LDA based calculations predict simila...