title: Field Effect in Graphene-Based van der Waals Heterostructures: Stacking Sequence Matters.
abstract: Stacked van der Waals (vdW) heterostructures where semiconducting two-dimensional (2D) materials are contacted by overlaid graphene electrodes enable atomically thin, flexible electronics. We use first-principles quantum transport simulations of graphene-contacted MoS2devices to show how the transistor effect critically depends on the stacking configuration relative to the gate electrode. We can trace this behavior to the stacking-dependent response of the contact region to the capacitive electric field induced by the gate. The contact resistance is a central parameter and our observation establishes an important design rule for ultrathin devices based on 2D atomic crystals.
authors.affiliation: Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology (DTU Nanotech), Technical University of Denmark , DK-2800, Kgs. Lyngby, Denmark.|QuantumWise A/S, Fruebjergvej 3, Postbox 4, DK-2100 Copenhagen, Denmark.
authors.forename: Daniele
authors.identifier: 0000-0002-3916-2168
authors.initials: D
authors.lastname: Stradi
authors.affiliation: Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology (DTU Nanotech), Technical University of Denmark , DK-2800, Kgs. Lyngby, Denmark.|ICN2 - Institut Català de Nanociència i Nanotecnologia , Campus UAB, 08193 Bellaterra, Spain.
authors.forename: Nick R
authors.identifier: 0000-0003-3038-1855
authors.initials: NR
authors.lastname: Papior
authors.affiliation: Department of Micro- and Nanotechnology (DTU Nanotech), Technical University of Denmark , DK-2800, Kgs. Lyngby, Denmark.
authors.forename: Ole
authors.initials: O
authors.lastname: Hansen
authors.affiliation: Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology (DTU Nanotech), Technical University of Denmark , DK-2800, Kgs. Lyngby, Denmark.
authors.forename: Mads
authors.identifier: 0000-0002-0126-9824
authors.initials: M
authors.lastname: Brandbyge
keywords: density functional theory; field-effect; graphene; nonequilibrium Green’s function; transport; vdW heterostructures