title: Resistivity of Rotated Graphite-Graphene Contacts.
abstract: Robust electrical contact of bulk conductors to two-dimensional (2D) material, such as graphene, is critical to the use of these 2D materials in practical electronic devices. Typical metallic contacts to graphene, whether edge or areal, yield a resistivity of no better than 100 Ω μm but are typically >10 kΩ μm. In this Letter, we employ single-crystal graphite for the bulk contact to graphene instead of conventional metals. The graphite contacts exhibit a transfer length up to four-times longer than in conventional metallic contacts. Furthermore, we are able to drive the contact resistivity to as little as 6.6 Ω μm(2) by tuning the relative orientation of the graphite and graphene crystals. We find that the contact resistivity exhibits a 60° periodicity corresponding to crystal symmetry with additional sharp decreases around 22° and 39°, which are among the commensurate angles of twisted bilayer graphene.
authors.affiliation: Department of Electrical Engineering and ‡Department of Physics, Columbia University , New York, New York 10027, United States.
authors.forename: Tarun
authors.initials: T
authors.lastname: Chari
authors.affiliation: Department of Electrical Engineering and ‡Department of Physics, Columbia University , New York, New York 10027, United States.
authors.forename: Rebeca
authors.initials: R
authors.lastname: Ribeiro-Palau
authors.affiliation: Department of Electrical Engineering and ‡Department of Physics, Columbia University , New York, New York 10027, United States.
authors.forename: Cory R
authors.initials: CR
authors.lastname: Dean
authors.affiliation: Department of Electrical Engineering and ‡Department of Physics, Columbia University , New York, New York 10027, United States.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Shepard
keywords: Graphene; commensurate angles; contact resistivity; graphite