Spin wave scattering and interface magnetism in superconducting-ferromagnet-superconducting hybrid structures

In this work we report on interlayer spin-polarized transport studies carried out on YBa2Cu3O7-delta/La2/3Sr1/3MnO3/YBa2Cu3O7-delta thin film multilayers. Anisotropic YBa2Cu3O7-delta high-temperature superconductors (YBCO) and the manganite La2/3Sr1/3MnO3 (LSMO) are layered metallic systems where the c-axis interlayer current transport occurs via sequential tunneling of charge carriers. The temperature dependence of the resistance R(T) for different applied fields shows that these heterostructures are clearly influenced by both the insulator-to-metal transition of the LSMO layers at similar to 320 K and the stripe fluctuations in the conductivity of the YBCO layers at the onset of electronic inhomogeneity at similar to 210 K. Furthermore, the tunneling of spin-polarized charge carriers between the YBCO layers through LSMO showed sharp switching between the high and low resistance states, which we assume corresponds to antiparallel and parallel alignments of the magnetic (spin) moments of these hybrid structures. The investigation of these promising hybrid structures is aimed at understanding the science of the new spin-based devices, laying the foundation for a new generation of ultrafast, nonvolatile electronics. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3076544]