title: Switching Behaviors of Graphene-Boron Nitride Nanotube Heterojunctions.
abstract: High electron mobility of graphene has enabled their application in high-frequency analogue devices but their gapless nature has hindered their use in digital switches. In contrast, the structural analogous, h-BN sheets and BN nanotubes (BNNTs) are wide band gap insulators. Here we show that the growth of electrically insulating BNNTs on graphene can enable the use of graphene as effective digital switches. These graphene-BNNT heterojunctions were characterized at room temperature by four-probe scanning tunneling microscopy (4-probe STM) under real-time monitoring of scanning electron microscopy (SEM). A switching ratio as high as 10(5) at a turn-on voltage as low as 0.5 V were recorded. Simulation by density functional theory (DFT) suggests that mismatch of the density of states (DOS) is responsible for these novel switching behaviors.
authors.affiliation: Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931, USA.
authors.forename: Vyom
authors.initials: V
authors.lastname: Parashar
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6487, USA.
authors.forename: Corentin P
authors.initials: CP
authors.lastname: Durand
authors.affiliation: Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931, USA.
authors.forename: Boyi
authors.initials: B
authors.lastname: Hao
authors.affiliation: Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931, USA.
authors.forename: Rodrigo G
authors.initials: RG
authors.lastname: Amorim
authors.affiliation: Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931, USA.
authors.forename: Ravindra
authors.initials: R
authors.lastname: Pandey
authors.affiliation: Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931, USA.
authors.forename: Bishnu
authors.initials: B
authors.lastname: Tiwari
authors.affiliation: Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931, USA.
authors.forename: Dongyan
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, NM 87185.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6487, USA.
authors.forename: An-Ping
authors.initials: AP
authors.lastname: Li
authors.affiliation: Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931, USA.
authors.forename: Yoke Khin
authors.initials: YK
authors.lastname: Yap