title: Negative differential resistance effect in planar graphene nanoribbon break junctions.
abstract: Graphene is an interesting material with a number of desirable electrical properties. Graphene-based negative differential resistance (NDR) devices hold great potential for enabling the implementation of several elements required in electronic circuits and systems. In this article we propose a novel device structure that exhibits NDR using single layer graphene that is able to be fabricated using standard lithography techniques. Using theoretical simulation, we show that graphene nanoribbon (GNR) junctions exhibit NDR effect if a gap is introduced in the structure in the transport direction of the ribbon. Using standard lithography techniques, we produce a GNR and use electro-migration to create a nanogap by breaking the GNR device. Scanning electron microscopy images show the formation of a tunnel gap. The predicted NDR phenomenon is experimentally verified in the current-voltage characteristic of the device. The linear and non-linear characteristics of the I-V responses before and after breakdown confirm that the NDR effect arises from the tunnel gap.
authors.affiliation: Centre for Neural Engineering, Bld 261, 203 Bouverie St and The University of Melbourne, Parkville, VIC 3010, Australia.
authors.forename: Phuong Duc
authors.initials: PD
authors.lastname: Nguyen
authors.forename: Thanh Cong
authors.initials: TC
authors.lastname: Nguyen
authors.forename: Faruque M
authors.initials: FM
authors.lastname: Hossain
authors.forename: Duc Hau
authors.initials: DH
authors.lastname: Huynh
authors.forename: Robin
authors.initials: R
authors.lastname: Evans
authors.forename: Efstratios
authors.initials: E
authors.lastname: Skafidas