title: Spin-orbit torque magnetization switching controlled by geometry.
abstract: Magnetization reversal by an electric current is essential for future magnetic data storage technology, such as magnetic random access memories. Typically, an electric current is injected into a pillar-shaped magnetic element, and switching relies on the transfer of spin momentum from a ferromagnetic reference layer (an approach known as spin-transfer torque). Recently, an alternative technique has emerged that uses spin-orbit torque (SOT) and allows the magnetization to be reversed without a polarizing layer by transferring angular momentum directly from the crystal lattice. With spin-orbit torque, the current is no longer applied perpendicularly, but is in the plane of the magnetic thin film. Therefore, the current flow is no longer restricted to a single direction and can have any orientation within the film plane. Here, we use Kerr microscopy to examine spin-orbit torque-driven domain wall motion in Co/AlOx wires with different shapes and orientations on top of a current-carrying Pt layer. The displacement of the domain walls is found to be highly dependent on the angle between the direction of the current and domain wall motion, and asymmetric and nonlinear with respect to the current polarity. Using these insights, devices are fabricated in which magnetization switching is determined entirely by the geometry of the device.
authors.affiliation: University of Grenoble Alpes INAC-SPINTEC, Grenoble F-38000, France.|CNRS INAC-SPINTEC, Grenoble F-38000, France.|CEA INAC-SPINTEC, Grenoble F-38000, France.
authors.forename: C K
authors.initials: CK
authors.lastname: Safeer
authors.affiliation: University of Grenoble Alpes INAC-SPINTEC, Grenoble F-38000, France.|CNRS INAC-SPINTEC, Grenoble F-38000, France.|CEA INAC-SPINTEC, Grenoble F-38000, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Jué
authors.affiliation: University of Grenoble Alpes INAC-SPINTEC, Grenoble F-38000, France.|CNRS INAC-SPINTEC, Grenoble F-38000, France.|CEA INAC-SPINTEC, Grenoble F-38000, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Lopez
authors.affiliation: University of Grenoble Alpes INAC-SPINTEC, Grenoble F-38000, France.|CNRS INAC-SPINTEC, Grenoble F-38000, France.|CEA INAC-SPINTEC, Grenoble F-38000, France.
authors.forename: Liliana
authors.initials: L
authors.lastname: Buda-Prejbeanu
authors.affiliation: University of Grenoble Alpes INAC-SPINTEC, Grenoble F-38000, France.|CNRS INAC-SPINTEC, Grenoble F-38000, France.|CEA INAC-SPINTEC, Grenoble F-38000, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Auffret
authors.affiliation: University of Grenoble Alpes INAC-SPINTEC, Grenoble F-38000, France.|CNRS Institut Néel, 38042 Grenoble, France.
authors.forename: Stefania
authors.initials: S
authors.lastname: Pizzini
authors.affiliation: University of Grenoble Alpes INAC-SPINTEC, Grenoble F-38000, France.|CNRS INAC-SPINTEC, Grenoble F-38000, France.|CEA INAC-SPINTEC, Grenoble F-38000, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Boulle
authors.affiliation: University of Grenoble Alpes INAC-SPINTEC, Grenoble F-38000, France.|CNRS INAC-SPINTEC, Grenoble F-38000, France.|CEA INAC-SPINTEC, Grenoble F-38000, France.
authors.forename: Ioan Mihai
authors.initials: IM
authors.lastname: Miron
authors.affiliation: University of Grenoble Alpes INAC-SPINTEC, Grenoble F-38000, France.|CNRS INAC-SPINTEC, Grenoble F-38000, France.|CEA INAC-SPINTEC, Grenoble F-38000, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Gaudin