title: Reversal of spin polarization in Fe/GaAs (001) driven by resonant surface states: first-principles calculations.
abstract: A minority-spin resonant state at the Fe/GaAs(001) interface is predicted to reverse the spin polarization with the voltage bias of electrons transmitted across this interface. Using a Green's function approach within the local spin-density approximation, we calculate the spin-dependent current in a Fe/GaAs/Cu tunnel junction as a function of the applied bias voltage. We find a change in sign of the spin polarization of tunneling electrons with bias voltage due to the interface minority-spin resonance. This result explains recent experimental data on spin injection in Fe/GaAs contacts and on tunneling magnetoresistance in Fe/GaAs/Fe magnetic tunnel junctions.
authors.affiliation: Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA. achantis@lanl.gov
authors.forename: Athanasios N
authors.initials: AN
authors.lastname: Chantis
authors.forename: Kirill D
authors.initials: KD
authors.lastname: Belashchenko
authors.forename: Darryl L
authors.initials: DL
authors.lastname: Smith
authors.forename: Evgeny Y
authors.initials: EY
authors.lastname: Tsymbal
authors.forename: Mark
authors.initials: M
authors.lastname: van Schilfgaarde
authors.forename: Robert C
authors.initials: RC
authors.lastname: Albers