We use density functional theory calculations to show that the ${\mathrm{LaAlO}}_3|{\mathrm{SrTiO}}_3$ interface between insulating perovskite oxides is borderline in satisfying the Stoner criterion for itinerant ferromagnetism and explore other oxide combinations with a view to satisfying it more amply. The larger lattice parameter of a ${\mathrm{LaScO}}_3|{\mathrm{BaTiO}}_3$ interface is found to be less favorable than the greater interface distortion of ${\mathrm{LaAlO}}_3|{\mathrm{CaTiO}}_3$. Compared to ${\mathrm{LaAlO}}_3|{\mathrm{SrTiO}}_3$, the latter is predicted to exhibit robust magnetism with a larger saturation moment and a higher Curie temperature. Our results provide support for a “two phase” picture of coexistent superconductivity and ferromagnetism.

• Received 10 June 2014

DOI:https://doi.org/10.1103/PhysRevLett.113.127201