title: Determination of the spin torque non-adiabaticity in perpendicularly magnetized nanowires.
abstract: Novel nanofabrication methods and the discovery of an efficient manipulation of local magnetization based on spin polarized currents has generated a tremendous interest in the field of spintronics. The search for materials allowing for fast domain wall dynamics requires fundamental research into the effects involved (Oersted fields, adiabatic and non-adiabatic spin torque, Joule heating) and possibilities for a quantitative comparison. Theoretical descriptions reveal a material and geometry dependence of the non-adiabaticity factor β, which governs the domain wall velocity. Here, we present two independent approaches for determining β: (i) measuring the dependence of the dwell times for which a domain wall stays in a metastable pinning state on the injected current and (ii) the current-field equivalence approach. The comparison of the deduced β values highlights the problems of using one-dimensional models to describe two-dimensional dynamics and allows us to ascertain the reliability, robustness and limits of the approaches used.
authors.affiliation: Fachbereich Physik, Universität Konstanz, Konstanz, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Heinen
authors.forename: D
authors.initials: D
authors.lastname: Hinzke
authors.forename: O
authors.initials: O
authors.lastname: Boulle
authors.forename: G
authors.initials: G
authors.lastname: Malinowski
authors.forename: H J M
authors.initials: HJ
authors.lastname: Swagten
authors.forename: B
authors.initials: B
authors.lastname: Koopmans
authors.forename: C
authors.initials: C
authors.lastname: Ulysse
authors.forename: G
authors.initials: G
authors.lastname: Faini
authors.forename: B
authors.initials: B
authors.lastname: Ocker
authors.forename: J
authors.initials: J
authors.lastname: Wrona
authors.forename: M
authors.initials: M
authors.lastname: Kläui