title: Negative spin polarization and large tunneling magnetoresistance in epitaxial Co/SrTiO(3)/Co magnetic tunnel junctions.
abstract: We perform an ab initio study of spin-polarized tunneling in epitaxial Co/SrTiO(3)/Co magnetic tunnel junctions with bcc Co(001) electrodes. We predict a large tunneling magnetoresistance in these junctions, originating from a mismatch in the majority- and minority-spin bands both in bulk bcc Co and at the Co/SrTiO(3)/Co interface. The intricate complex band structure of SrTiO(3) enables efficient tunneling of the minority d electrons which causes the spin polarization of the Co/SrTiO(3)/Co interface to be negative in agreement with experimental data. Our results indicate that epitaxial Co/SrTiO(3)/Co magnetic tunnel junctions with bcc Co(001) electrodes are a viable alternative for device applications.
authors.affiliation: Department of Physics and Astronomy and Center for Materials Research and Analysis, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Velev
authors.forename: K D
authors.initials: KD
authors.lastname: Belashchenko
authors.forename: D A
authors.initials: DA
authors.lastname: Stewart
authors.forename: M
authors.initials: M
authors.lastname: van Schilfgaarde
authors.forename: S S
authors.initials: SS
authors.lastname: Jaswal
authors.forename: E Y
authors.initials: EY
authors.lastname: Tsymbal