TY - JOUR TI - A nanochannel with an embedded transverse graphene tunneling electrode for molecular probing and as a future tool for DNA sequencing DO - https://doi.org/doi:10.7282/T38914XT PY - 2011 AB - Single layer graphene, as a one-atom-thick highly conductive layer, is an exciting candidate for highly localized tunneling measurements because it is sufficiently thin to resolve a single molecule. We have fabricated graphene tunneling junctions confined within a nanochannel to explore the feasibility of developing a single-molecule sequencing tool for deoxyribonucleic acid (DNA). The unprecedented thinness of graphene electrodes allows to overcome the problems encountered using metallic electrodes, which are too bulky for single-molecule resolution. By confining of the molecule in a nanochannel, a long and narrow structure through which it can be dragged electrophoretically, it is possible to slow down the DNA sufficiently to achieve single base translocation. We show an experimental realization of the first steps towards a new graphene sequencing device. First, we present a new experimental technique for the production of nanogaps in a sheet of graphene. Applying a high current density in a graphene strip removes material from the strip resulting in the formation of nanogaps and tips. Starting from graphene grown by Chemical Vapor Deposition (CVD), we fabricate those structures. We show transport measurements of graphene devices in helium, air and vacuum demonstrating the realization of tunneling gaps. Second, we embed graphene tunneling junctions in a nanochannel and measure tunneling currents through various liquids. Using Simmons' model we calculate the work function between graphene and those liquids. Third we present evidence for inelastic tunneling through different molecules especially Rhodamine B and Adenosine monophosphate. We compare the results with data from optical spectroscopy. KW - Physics and Astronomy KW - Graphene KW - Nucleotide sequence LA - eng ER -