title: Current-Induced Spin Polarization in Topological Insulator-Graphene Heterostructures.
abstract: Further development of the field of all-electric spintronics requires the successful integration of spin transport channels with spin injector/generator elements. While with the advent of graphene and related 2D materials high performance spin channel materials are available, the use of nanostructured spin generators remains a major challenge. Especially promising for the latter purpose are 3D topological insulators, whose 2D surface states host massless Dirac Fermions with spin-momentum locking. Here, we demonstrate injection of spin-polarized current from a topological insulator into graphene, enabled by its intimate coupling to an ultrathin Bi2Te2Se nanoplatelet within a van der Waals epitaxial heterostructure. The spin switching signal, whose magnitude scales inversely with temperature, is detectable up to ∼15 K. Our findings establish topological insulators as prospective future components of spintronic devices wherein spin manipulation is achieved by purely electrical means.
authors.affiliation: Max Planck Institute for Solid State Research , Heisenbergstrasse 1, D-70569 Stuttgart, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Vaklinova
authors.affiliation: Max Planck Institute for Solid State Research , Heisenbergstrasse 1, D-70569 Stuttgart, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Hoyer
authors.affiliation: Max Planck Institute for Solid State Research , Heisenbergstrasse 1, D-70569 Stuttgart, Germany.
authors.forename: Marko
authors.initials: M
authors.lastname: Burghard
authors.affiliation: Max Planck Institute for Solid State Research , Heisenbergstrasse 1, D-70569 Stuttgart, Germany.|Institut de Physique de la Matière Condensée, Ecole Polytechnique Fédérale de Lausanne , CH-1015 Lausanne, Switzerland.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kern
keywords: Topological insulators; graphene; spintronics; van der Waal epitaxy