Stabilization of high Curie temperature in manganite/ruthenate superlattices with ultrathin layers
La0.7Sr0.3MnO3/SrRuO3 superlattices were grown on SrTiO3(100) crystals by pulsed-laser deposition. These superlattices exhibited magnetization processes with an intricate interplay between magnetocrystalline anisotropy, magnitude of layer magnetization, spin confinement and antiferromagnetic interlayer coupling. The Curie temperature of the La0.7Sr0.3MnO3 layers so thin as two unit cells was stabilized close to room temperature. Manganite/ruthenate interfaces may be studied as a model system for interfacial reconstruction and charge transfer in a highly correlated ferromagnetic system.