All-Manganite Tunnel Junctions with Interface-Induced Barrier Magnetism

The recent discovery of several unexpected phases at complex oxide interfaces is providing new insights into the physics of strongly correlated electron systems. The possibility of tailoring the electronic structure of such interfaces has triggered a great technological drive to functionalize them into devices. In this communication, we describe an alternative strategy to produce spin filtering by inducing a ferromagnetic insulating state in an ultrathin antiferromagnetic layer in contact with a ferromagnetic layer. This artificially induced spin filtering persists up to relatively high temperatures and operates at high applied bias voltages. The results suggest that after playing a key role in exchange-bias for spin-valves, uncompensated moments at engineered antiferromagnetic interfaces represent a novel route for generating highly spin-polarized currents with antiferromagnets.\\[4pt] Work done in collaboration with M. Bibes, C. Carr\'{e}t\'{e}ro, A. Barth\'{e}l\'{e}my (Unit\'{e} Mixte de Physique CNRS/Thales, Campus de Polytechnique, 1, Avenue A. Fresnel, 91767 Palaiseau (France) and Universit\'{e} Paris-Sud, 91045 Orsay (France)), F.A. Cuellar, C. Visani, A. Rivera-Calzada, , C. Le\'{o}n, J. Santamaria (Grupo de F\'{\i}sica de Materiales Complejos, Universidad Complutense de Madrid, 28040 Madrid (Spain)), M.J. Calder\'{o}n, L. Brey (Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid (Spain)), K. March, M. Walls, D. Imhoff (Laboratoire de Physique des Solides, CNRS, Universit\'{e} Paris-Sud, 91405 Orsay (France)), R. Lopez Anton, T.R. Charlton (ISIS, Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX (United Kingdom)), E. Iborra (Universidad Polit\'{e}cnica de Madrid, Escuela T\'{e}cnica Superior de Ingenieros de Telecomunicaciones, 28040 Madrid ( Spain)), F. Ott (L\'{e}on Brillouin, CEA/CNRS, UMR 12, 91191 Gif-sur-Yvette (France)).