title: Controlling spin relaxation in hexagonal BN-encapsulated graphene with a transverse electric field.
abstract: We experimentally study the electronic spin transport in hexagonal BN encapsulated single layer graphene nonlocal spin valves. The use of top and bottom gates allows us to control the carrier density and the electric field independently. The spin relaxation times in our devices range up to 2 ns with spin relaxation lengths exceeding 12 μm even at room temperature. We obtain that the ratio of the spin relaxation time for spins pointing out-of-plane to spins in-plane is τ(⊥)/τ(||) ≈ 0.75 for zero applied perpendicular electric field. By tuning the electric field, this anisotropy changes to ≈ 0.65 at 0.7 V/nm, in agreement with an electric field tunable in-plane Rashba spin-orbit coupling.
authors.affiliation: Physics of Nanodevices, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
authors.forename: M H D
authors.initials: MH
authors.lastname: Guimarães
authors.affiliation: Physics of Nanodevices, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
authors.forename: P J
authors.initials: PJ
authors.lastname: Zomer
authors.affiliation: Physics of Nanodevices, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Ingla-Aynés
authors.affiliation: Physics of Nanodevices, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
authors.forename: J C
authors.initials: JC
authors.lastname: Brant
authors.affiliation: Physics of Nanodevices, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
authors.forename: N
authors.initials: N
authors.lastname: Tombros
authors.affiliation: Physics of Nanodevices, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
authors.forename: B J
authors.initials: BJ
authors.lastname: van Wees