Engineered interface of magnetic oxides

Interface-selective probing of magnetism is a key issue for the design and realization of spin-electronic junction devices. Here, magnetization-induced second-harmonic generation was used to probe the local magnetic properties at the interface of the perovskite ferromagnet La0.6Sr0.4MnO3 with nonmagneticat the interface of the perovskite ferromagnet La0.6Sr0.4MnO3 with nonmagnetic insulating layers, as used in spin-tunnel junctions. We show that by grading the doping pro. le on an atomic scale at the interface, robust ferromagnetism can be realized around room temperature. The results should lead to improvements in the performance of spin-tunnel junctions.