title: Spin transport and Hanle effect in silicon nanowires using graphene tunnel barriers.
abstract: Spin-based devices offer non-volatile, scalable, low power and reprogrammable functionality for emerging device technologies. Here we fabricate nanoscale spintronic devices with ferromagnetic metal/single-layer graphene tunnel barriers used to generate spin accumulation and spin currents in a silicon nanowire transport channel. We report the first observation of spin precession via the Hanle effect in both local three-terminal and non-local spin-valve geometries, providing a direct measure of spin lifetimes and confirmation of spin accumulation and pure spin transport. The use of graphene as the tunnel barrier provides a low-resistance area product contact and clean magnetic switching characteristics, because it smoothly bridges the nanowire and minimizes complicated magnetic domains that otherwise compromise the magnetic behaviour. Utilizing intrinsic two-dimensional layers such as graphene or hexagonal boron nitride as tunnel contacts on nanowires offers many advantages over conventional materials deposited by vapour deposition, enabling a path to highly scaled electronic and spintronic devices.
authors.affiliation: Naval Research Laboratory, Washington, DC 20375, USA.
authors.forename: O M J
authors.initials: OM
authors.lastname: van 't Erve
authors.affiliation: Naval Research Laboratory, Washington, DC 20375, USA.
authors.forename: A L
authors.initials: AL
authors.lastname: Friedman
authors.affiliation: Naval Research Laboratory, Washington, DC 20375, USA.
authors.forename: C H
authors.initials: CH
authors.lastname: Li
authors.affiliation: Naval Research Laboratory, Washington, DC 20375, USA.
authors.forename: J T
authors.initials: JT
authors.lastname: Robinson
authors.affiliation: Northwestern University, Evanston, IL 60208, USA.
authors.forename: J
authors.initials: J
authors.lastname: Connell
authors.affiliation: Northwestern University, Evanston, IL 60208, USA.
authors.forename: L J
authors.initials: LJ
authors.lastname: Lauhon
authors.affiliation: Naval Research Laboratory, Washington, DC 20375, USA.
authors.forename: B T
authors.initials: BT
authors.lastname: Jonker