title: Oxygen-vacancy-induced diffusive scattering in Fe/MgO/Fe magnetic tunnel junctions.
abstract: By first principles analysis, we systematically investigate effects of oxygen vacancies (OV) in the MgO barrier of Fe/MgO/Fe magnetic tunnel junctions. The interchannel diffusive scattering by disordered OVs located at or near the Fe/MgO interface drastically reduces the tunnel magnetoresistance ratio (TMR) from the ideal theoretical limit to the presently observed much smaller experimental range. Interior OVs are far less important in influencing TMR, but they significantly increase the junction resistance. Filling OV with nitrogen atoms restores TMR to near the ideal theoretical limit.
authors.affiliation: Centre for the Physics of Materials and Department of Physics, McGill University, Montreal, PQ H3A 2T8, Canada.
authors.forename: Youqi
authors.initials: Y
authors.lastname: Ke
authors.forename: Ke
authors.initials: K
authors.lastname: Xia
authors.forename: Hong
authors.initials: H
authors.lastname: Guo