title: Highly confined spin-polarized two-dimensional electron gas in SrTiO3/SrRuO3 superlattices.
abstract: We report first-principles characterization of the structural and electronic properties of (SrTiO3)5/(SrRuO3)1 superlattices. We show that the system exhibits a spin-polarized two-dimensional electron gas, extremely confined to the 4d orbitals of Ru in the SrRuO3 layer. Every interface in the superlattice behaves as a minority-spin half-metal ferromagnet, with a magnetic moment of μ=2.0μ(B)/SrRuO3 unit. The shape of the electronic density of states, half-metallicity, and magnetism are explained in terms of a simplified tight-binding model, considering only the t(2g) orbitals plus (i) the bidimensionality of the system and (ii) strong electron correlations.
authors.affiliation: Departamento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Cantabria Campus Internacional, Avenida de los Castros s/n, 39005 Santander, Spain.
authors.forename: Marcos
authors.initials: M
authors.lastname: Verissimo-Alves
authors.forename: Pablo
authors.initials: P
authors.lastname: García-Fernández
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Bilc
authors.forename: Philippe
authors.initials: P
authors.lastname: Ghosez
authors.forename: Javier
authors.initials: J
authors.lastname: Junquera